STANDARD BANK NOT REFUNDING MY MONEY

On the 13 Dec 2014, I called the bank to enquire about the settlement amount on my car. The lady that assisted me gave me the settlement amount over the phone and promised to email me settlement letter which she did. The settlement amount was R11029.00. That week end my emails were not working, however I decided to make an EFT payment anyway. Unfortunately for me, I forgot the amount she gave me so I made a payment of R12000 instead. On the 15 Dec 2014 I managed to access my emails and I learnt the payment was extra by R971. On the same day I sent an email requesting that the money be refunded and I got no reply from the bank. I called in and held the phone for 15 min without an answer and I gave up.Sent follow up email and there was still no answer. To cut the long story short since that time to date I still have not received my money. I got two reference numbers for the calls they somehow managed to answer. Service Request No:*** and ***. I called these people so many times, I don't have the energy anymore.