A bot running in privacy mode will not receive all messages that people send to the group . Instead, it will only receive: Messages that start with a slash ‘/’ (see Commands above) Replies to the bot’s own messages.
Read moreHow do you make a private Telegram bot accessible by owner?
The only way is using a custom command like /password to send a password to the bot and then keep the chat id of the client (when password is correct of course …).2 Eyl 2017
Read moreHow can I protect my Telegram bot?
To help your Telegram bot be as secure as possible, limit access to only the IPs Telegram is sending updates from . You can also limit IP access on the server side.
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