Telegram bot send message problems after some days

Question

I have some problem with my telegram message, it's overview of problem:

You will pass /start command my bot started sending messages, but after some days it will stop sending messages, if client pass some message client bot again starts sending messages, what can I do for define after how much days it will stop, does it documentation anywhere? maybe some configurations are wrong? who have such kind of situation pls, reply?

also I always this api call for sending messages:

https://api.telegram.org/bot{TELEGRAM_BOT}/sendMessage?disable_web_page_preview=false&chat_id=$chat_id&text={TEXT}

Answer 1

When a telegram group is migrated to supergroup, the chat id for the group changes. Do check if you are sending your message to the new chat_id.

Answer 2

if user stops the bot you cant send any messages to him/her and you receive a error like this:

[Error]: Bot was blocked by the user

i use the bots about the beginning and i never saw something like this happens.