dissatisfied client

I went to the bank on the 3rd of this month to settle my credit card bill. On arrival I was helped by a coloured lady without a name tag. She transferred 3000 from my savings account into the credit card knowing I only owe 1900 and told me she had to do so cause that's what's required. I called the call centre the following day after receiving no notifications only for them to tell me no transactions took place. I then went back to the branch only for the lady to tell me she's processing things and I would get my refund of 1100 the following day before close of business. Its been days now I went to the branch twice and I still haven't received my money.