I think what happened here is someone first transferred money to OP's bank account, and then OP used the money he received to buy bitcoins on an exchange.
If this is the case, and a hacker has logged in to someone else's account and transferred money to OP, rather than sending the logn details to OP, then if I were OP I'd be asking my lawyers to contact the sending bank and request the activity logs on that account. It's a very slim chance, but perhaps IP logs might help to show that it wasn't you who stolen that money. If you can match the bank login IPs to the scammer's Telegram IP, then even better.
I have never used Telegram so no idea how difficult it would be to get them to release IP data.