Randomly debited R82 526 for a credit card “payment”

I transferred R70 000 into my cheque account on 27 Nov which I cannot use as my own money because fnb suddenly debited R82 526 from my account! One, I don’t owe them such an amount, two they had no authority to debit my account as they please! I’m stuck in Singapore as a broke person thanks to fnb for the inconvenience. No I don’t want to speak to anyone, I WANT MY MONEY