Bad service

Goo day.

I have a huge problem here, on the 25th of January 2020, one guy bought jean and a t shirt from my friend and cash of 2500 was transferred into my account by the buyer since he didn't have FNB because my friend uses FNB, now I tried to make a widrawall last night then I was told that my account had insufficient funds but I have money in that account, later I called the call center I was advised that my card is stopped due to unauthorized transfer that was made in to my account on the 25th of January so I was advised to visit the branch, I've been there and I ddnt get any help I was advised to contact the person that transferred money into my account and speak to him, now my problem is that I have debt to pay and my rent is due, as much as I don't even have that person's number since he was just purchasing goods from my friend and I was goin to try and retrieve the number on my statement so what should I do now?