If accounts are being banned en masse on the first launch, double-check everything below:
Before launching, make sure that no other Telegram process is open in Task Manager, if it is open, terminate all processes.
Run accounts on the latest version of Telegram.
Log in with a clean private proxy (ideally mobile).
Do not use free services for IP change.
Do not log into multiple accounts under one IP.
Do not change your 2FA password on ALL accounts at once, you may get banned!
Accounts are intended for use in the official Telagram Portable client, the guarantee of replacing invalid is provided only for it!
Recommendations:
1 account = 1 proxy
Buy a small number of accounts and test them first,
Ctrl + Q - quickly close Telegram