Telegram picks up on phone numbers in your contact list. Users can also set a username unique and only one user or even with a different phone number.
Telegram offers privacy and security options that allow account holders to limit calls, messages, or other engagements. Under the security and privacy settings is an option to block users.
If someone deletes their Telegram account, all messages and contacts are flushed out, and you are not able to send any more messages to this account.
Telegram respects its users and is justified to take actions like banning users who violate rules and privacy, such as sharing nudity, hate speech, and spreading false information among others.
Your messaging may not be successful because of either your internet connection or your app or because you are misspelling the name or sending the message to the wrong number.
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