If you deactivate or delete your telegram account, all your messages, groups, channels, contacts will be removed. To delete telegram account (Android, iOS, Windows Phone, Desktop) do as follows:
1. Open the Telegram Deactivation Page on a desktop browser.2. On the opened page, enter the phone number associated with the account you want to complete deactivate and delete. 3. Tap the Next button and then you are asked to enter a password. (The password has already been sent from Telegram. Check out you Telegram on your phone and look for a new message from the Telegram.)** Note that the message is like: You can use this password to log in on the Telegram website: YOUR PASSWORD4. Now you need to confirm the “Delete Your Account?” message. You may also type the reasons to leave the Telegram.5. You successfully deactivated your Telegram account across all your platforms.
NOTE THAT THIS PROCEDURE CANNOT BE UNDONE and as soon as you delete or deactivate Telegram account, all your history (messages, contacts, groups, channels) will be GONE forever.
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