Capitec chose wrong account for my deposit

I had a bank account with Capitec ********** 488 which I then stopped using and opened a new one ********** 329, then a colleague deposited money for me by presenting the bank with the 14..... account number, the teller at Ba***eng Mall chose to deposit the money in my 13....... on her own accord, the deposit was R1000 then I got a notification that R940 has gone off, so now they say they cant reverse the payment to the right account because I was owing the bank, but why didn't they give me a chance to settle the account instead of just taking the money, so the tellers negligence is now covered by the fact that my account was in arrears? This is unfair and unacceptable.