Embarrassment in front of customers

On Monday I went to Spar @ van der Hoff street branch to buy food. To my surprise the terminal decline my transaction saying insufficient funds. I went outside on the ATM and check my balance. There was money in the bank account. I went again to purchase the food.the same problem. Insufficient funds. I went to Standard bank quagga (Pretoria West). Lodge my complains about the embarrassment. The consultant check and couldn't find the problem and lodge a phone call, in respond they told her to let me change the pin, we did change the pin and went to outside ATM and the problem persists insufficient funds. She issued me with a new debit card and a new pin. I went outside to the ATM. It gave me the same problem insufficient fund. I left all my cards so to solve the problem. To my surprise I'm being charge for all the transactions I was making under their instructions. I ask for them to be reversed. They only reversed two transactions for balance enquiry. Up to today I haven heard anything from the bank what is the problem and when they gonna reverse the charges for that day. I left the