diff --git a/build/lib/evolutionapi/client.py b/build/lib/evolutionapi/client.py
index 991d756..7bfdbd7 100644
--- a/build/lib/evolutionapi/client.py
+++ b/build/lib/evolutionapi/client.py
@@ -1,4 +1,5 @@
 import requests
+from requests_toolbelt import MultipartEncoder
 from .exceptions import EvolutionAuthenticationError, EvolutionNotFoundError, EvolutionAPIError
 from .services.instance import InstanceService
 from .services.instance_operations import InstanceOperationsService
@@ -62,11 +63,43 @@ class EvolutionClient:
         response = requests.get(url, headers=self._get_headers(instance_token))
         return self._handle_response(response)
 
-    def post(self, endpoint: str, data: dict = None, instance_token: str = None):
-        """Faz uma requisição POST."""
-        url = self._get_full_url(endpoint)
-        response = requests.post(url, headers=self._get_headers(instance_token), json=data)
-        return self._handle_response(response)
+    def post(self, endpoint: str, data: dict = None, instance_token: str = None, files: dict = None):
+        url = f'{self.base_url}/{endpoint}'
+        headers = self._get_headers(instance_token)
+        
+        if files:
+            # Remove o Content-Type do header quando enviando arquivos
+            if 'Content-Type' in headers:
+                del headers['Content-Type']
+            
+            # Prepara os campos do multipart
+            fields = {}
+            
+            # Adiciona os campos do data
+            for key, value in data.items():
+                fields[key] = str(value) if not isinstance(value, (int, float)) else (None, str(value), 'text/plain')
+            
+            # Adiciona o arquivo
+            file_tuple = files['file']
+            fields['file'] = (file_tuple[0], file_tuple[1], file_tuple[2])
+            
+            # Cria o multipart encoder
+            multipart = MultipartEncoder(fields=fields)
+            headers['Content-Type'] = multipart.content_type
+            
+            response = requests.post(
+                url, 
+                headers=headers,
+                data=multipart
+            )
+        else:
+            response = requests.post(
+                url, 
+                headers=headers, 
+                json=data
+            )
+        
+        return response.json()
 
     def put(self, endpoint, data=None):
         """Faz uma requisição PUT."""
diff --git a/build/lib/evolutionapi/models/message.py b/build/lib/evolutionapi/models/message.py
index 739460f..cd4a82a 100644
--- a/build/lib/evolutionapi/models/message.py
+++ b/build/lib/evolutionapi/models/message.py
@@ -53,28 +53,34 @@ class MediaMessage(BaseMessage):
     def __init__(
         self,
         number: str,
-        mediatype: str,
-        mimetype: str,
-        caption: str,
-        media: str,
-        fileName: str,
-        delay: Optional[int] = None,
+        media: dict = None,
+        mediatype: Optional[str] = None,
+        caption: str = None,
+        mimetype: str = None,
+        fileName: str = None,
+        delay: Optional[Union[int, float, str]] = None,
         quoted: Optional[QuotedMessage] = None,
         mentionsEveryOne: Optional[bool] = None,
         mentioned: Optional[List[str]] = None
     ):
-        super().__init__(
-            number=number,
-            mediatype=mediatype,
-            mimetype=mimetype,
-            caption=caption,
-            media=media,
-            fileName=fileName,
-            delay=delay,
-            quoted=quoted.__dict__ if quoted else None,
-            mentionsEveryOne=mentionsEveryOne,
-            mentioned=mentioned
-        )
+        data = {
+            'number': number,
+            'mediatype': mediatype,
+            'caption': caption,
+            'mimetype': mimetype,
+            'fileName': fileName,
+            'quoted': quoted.__dict__ if quoted else None,
+            'mentionsEveryOne': mentionsEveryOne,
+            'mentioned': mentioned
+        }
+        
+        if delay is not None:
+            data['delay'] = delay
+        
+        if media and media != {}:
+            data['media'] = media
+            
+        super().__init__(**{k: v for k, v in data.items() if v is not None})
 
 class StatusMessage(BaseMessage):
     def __init__(
diff --git a/build/lib/evolutionapi/services/message.py b/build/lib/evolutionapi/services/message.py
index f151259..79efaae 100644
--- a/build/lib/evolutionapi/services/message.py
+++ b/build/lib/evolutionapi/services/message.py
@@ -1,70 +1,118 @@
 from typing import Union, BinaryIO
 from ..models.message import *
+from requests_toolbelt import MultipartEncoder
+import mimetypes
+import requests
 
 class MessageService:
     def __init__(self, client):
         self.client = client
 
     def send_text(self, instance_id: str, message: TextMessage, instance_token: str):
+        # Preparar os dados como JSON
+        data = {
+            'number': message.number,
+            'text': message.text
+        }
+        
+        if hasattr(message, 'delay') and message.delay is not None:
+            data['delay'] = message.delay
+        
+        # Usar o método post do cliente que já trata JSON corretamente
         return self.client.post(
             f'message/sendText/{instance_id}',
-            data=message.__dict__,
+            data=data,
             instance_token=instance_token
         )
 
     def send_media(self, instance_id: str, message: MediaMessage, instance_token: str, file: Union[BinaryIO, str] = None):
-        payload = {
-            'data': message.__dict__,
-            'instance_token': instance_token
+        # Preparar os dados do formulário
+        fields = {
+            'number': (None, message.number, 'text/plain'),
+            'mediatype': (None, message.mediatype, 'text/plain'),
+            'mimetype': (None, message.mimetype, 'text/plain'),
+            'caption': (None, message.caption, 'text/plain'),
+            'fileName': (None, message.fileName, 'text/plain'),
         }
         
+        # Adicionar delay apenas se existir
+        if hasattr(message, 'delay') and message.delay is not None:
+            fields['delay'] = (None, str(message.delay), 'text/plain; type=number')
+        
+        # Adicionar o arquivo se fornecido
         if file:
             if isinstance(file, str):
-                with open(file, 'rb') as f:
-                    payload['files'] = {'file': f}
+                mime_type = mimetypes.guess_type(file)[0] or 'application/octet-stream'
+                fields['file'] = ('file', open(file, 'rb'), mime_type)
             else:
-                payload['files'] = {'file': file}
-            
-        return self.client.post(
-            f'message/sendMedia/{instance_id}',
-            **payload
+                fields['file'] = ('file', file, 'application/octet-stream')
+        
+        # Criar o multipart encoder
+        multipart = MultipartEncoder(fields=fields)
+        
+        # Preparar os headers
+        headers = self.client._get_headers(instance_token)
+        headers['Content-Type'] = multipart.content_type
+        
+        # Fazer a requisição diretamente
+        url = f'{self.client.base_url}/message/sendMedia/{instance_id}'
+        response = requests.post(
+            url,
+            headers=headers,
+            data=multipart
         )
+        
+        return response.json()
 
     def send_ptv(self, instance_id: str, message: dict, instance_token: str, file: Union[BinaryIO, str] = None):
-        payload = {
-            'data': message,
-            'instance_token': instance_token
-        }
+        fields = {}
+        
+        # Adiciona todos os campos do message como text/plain
+        for key, value in message.items():
+            if key == 'delay' and value is not None:
+                fields[key] = (None, str(value), 'text/plain; type=number')
+            else:
+                fields[key] = (None, str(value), 'text/plain')
         
         if file:
             if isinstance(file, str):
-                with open(file, 'rb') as f:
-                    payload['files'] = {'file': f}
+                mime_type = mimetypes.guess_type(file)[0] or 'application/octet-stream'
+                fields['file'] = ('file', open(file, 'rb'), mime_type)
             else:
-                payload['files'] = {'file': file}
-            
-        return self.client.post(
-            f'message/sendPtv/{instance_id}',
-            **payload
-        )
+                fields['file'] = ('file', file, 'application/octet-stream')
+        
+        multipart = MultipartEncoder(fields=fields)
+        headers = self.client._get_headers(instance_token)
+        headers['Content-Type'] = multipart.content_type
+        
+        url = f'{self.client.base_url}/message/sendPtv/{instance_id}'
+        response = requests.post(url, headers=headers, data=multipart)
+        return response.json()
 
     def send_whatsapp_audio(self, instance_id: str, message: dict, instance_token: str, file: Union[BinaryIO, str] = None):
-        payload = {
-            'data': message,
-            'instance_token': instance_token
-        }
+        fields = {}
+        
+        # Adiciona todos os campos do message como text/plain
+        for key, value in message.items():
+            if key == 'delay' and value is not None:
+                fields[key] = (None, str(value), 'text/plain; type=number')
+            else:
+                fields[key] = (None, str(value), 'text/plain')
         
         if file:
             if isinstance(file, str):
-                with open(file, 'rb') as f:
-                    payload['files'] = {'file': f}
+                mime_type = mimetypes.guess_type(file)[0] or 'application/octet-stream'
+                fields['file'] = ('file', open(file, 'rb'), mime_type)
             else:
-                payload['files'] = {'file': file}
-            
-        return self.client.post(
-            f'message/sendWhatsAppAudio/{instance_id}',
-            **payload
-        )
+                fields['file'] = ('file', file, 'application/octet-stream')
+        
+        multipart = MultipartEncoder(fields=fields)
+        headers = self.client._get_headers(instance_token)
+        headers['Content-Type'] = multipart.content_type
+        
+        url = f'{self.client.base_url}/message/sendWhatsAppAudio/{instance_id}'
+        response = requests.post(url, headers=headers, data=multipart)
+        return response.json()
 
     def send_status(self, instance_id: str, message: StatusMessage, instance_token: str):
         return self.client.post(
@@ -73,17 +121,39 @@ class MessageService:
             instance_token=instance_token
         )
 
-    def send_sticker(self, instance_id: str, message: dict, instance_token: str):
-        return self.client.post(
-            f'message/sendSticker/{instance_id}',
-            data=message,
-            instance_token=instance_token
-        )
+    def send_sticker(self, instance_id: str, message: dict, instance_token: str, file: Union[BinaryIO, str] = None):
+        fields = {}
+        
+        # Adiciona todos os campos do message como text/plain
+        for key, value in message.items():
+            if key == 'delay' and value is not None:
+                fields[key] = (None, str(value), 'text/plain; type=number')
+            else:
+                fields[key] = (None, str(value), 'text/plain')
+        
+        if file:
+            if isinstance(file, str):
+                mime_type = mimetypes.guess_type(file)[0] or 'application/octet-stream'
+                fields['file'] = ('file', open(file, 'rb'), mime_type)
+            else:
+                fields['file'] = ('file', file, 'application/octet-stream')
+        
+        multipart = MultipartEncoder(fields=fields)
+        headers = self.client._get_headers(instance_token)
+        headers['Content-Type'] = multipart.content_type
+        
+        url = f'{self.client.base_url}/message/sendSticker/{instance_id}'
+        response = requests.post(url, headers=headers, data=multipart)
+        return response.json()
 
     def send_location(self, instance_id: str, message: LocationMessage, instance_token: str):
+        data = message.__dict__.copy()
+        if 'delay' in data and data['delay'] is not None:
+            data['delay'] = int(data['delay'])
+        
         return self.client.post(
             f'message/sendLocation/{instance_id}',
-            data=message.__dict__,
+            data=data,
             instance_token=instance_token
         )
 
@@ -102,22 +172,34 @@ class MessageService:
         )
 
     def send_poll(self, instance_id: str, message: PollMessage, instance_token: str):
+        data = message.__dict__.copy()
+        if 'delay' in data and data['delay'] is not None:
+            data['delay'] = int(data['delay'])
+        
         return self.client.post(
             f'message/sendPoll/{instance_id}',
-            data=message.__dict__,
+            data=data,
             instance_token=instance_token
         )
 
     def send_list(self, instance_id: str, message: ListMessage, instance_token: str):
+        data = message.__dict__.copy()
+        if 'delay' in data and data['delay'] is not None:
+            data['delay'] = int(data['delay'])
+        
         return self.client.post(
             f'message/sendList/{instance_id}',
-            data=message.__dict__,
+            data=data,
             instance_token=instance_token
         )
 
     def send_buttons(self, instance_id: str, message: ButtonMessage, instance_token: str):
+        data = message.__dict__.copy()
+        if 'delay' in data and data['delay'] is not None:
+            data['delay'] = int(data['delay'])
+        
         return self.client.post(
             f'message/sendButtons/{instance_id}',
-            data=message.__dict__,
+            data=data,
             instance_token=instance_token
         )
\ No newline at end of file
diff --git a/dist/evolutionapi-0.0.4.tar.gz b/dist/evolutionapi-0.0.4.tar.gz
deleted file mode 100644
index f9451f6..0000000
Binary files a/dist/evolutionapi-0.0.4.tar.gz and /dev/null differ
diff --git a/dist/evolutionapi-0.0.4-py3-none-any.whl b/dist/evolutionapi-0.0.5-py3-none-any.whl
similarity index 65%
rename from dist/evolutionapi-0.0.4-py3-none-any.whl
rename to dist/evolutionapi-0.0.5-py3-none-any.whl
index e5087e3..3a29bd5 100644
Binary files a/dist/evolutionapi-0.0.4-py3-none-any.whl and b/dist/evolutionapi-0.0.5-py3-none-any.whl differ
diff --git a/dist/evolutionapi-0.0.5.tar.gz b/dist/evolutionapi-0.0.5.tar.gz
new file mode 100644
index 0000000..5504967
Binary files /dev/null and b/dist/evolutionapi-0.0.5.tar.gz differ
diff --git a/evolutionapi.egg-info/PKG-INFO b/evolutionapi.egg-info/PKG-INFO
index f53f99e..3dac2b0 100644
--- a/evolutionapi.egg-info/PKG-INFO
+++ b/evolutionapi.egg-info/PKG-INFO
@@ -1,6 +1,6 @@
 Metadata-Version: 2.1
 Name: evolutionapi
-Version: 0.0.4
+Version: 0.0.5
 Summary: Client Python para a API Evolution
 Home-page: UNKNOWN
 Author: Davidson Gomes
diff --git a/setup.py b/setup.py
index c04518a..d4b2a66 100644
--- a/setup.py
+++ b/setup.py
@@ -2,7 +2,7 @@ from setuptools import setup, find_packages
 
 setup(
     name='evolutionapi',
-    version='0.0.4',
+    version='0.0.5',
     description='Client Python para a API Evolution',
     author='Davidson Gomes',
     author_email='contato@agenciadgcode.com',