Telegram Bot telepot bad request sending message to group chat

Question

I make a bot via @BotFather and I can send messages to me but when i tried to send messages to a group chat i get Bad Request Error 400.

• The group chat ID is checked with 3 bots.

import telepot

api_key = '123456789'
user_id = '123456'

bot = telepot.Bot(api_key)

msg = 'Hola, este es un mensaje de prueba.'

bot.sendMessage(user_id, msg)

I set the group setting enable. I added the bot to the group as Admin. I set the privacy settings disabled.