Pick n pay smart shopper

I had a really ****ty and embarrassing experience at pick n pay plumstead, I attempted to pay using my pick n pay smart shopper card with the credit facility. There is credit and payments are up to date, that day I had no other means to pay for my groceries, when I got to the till the card had declined due to “technical malfunction” when the manager attempted to phone the call center to find out what the problem is as according to her I was not the only shopper it had a happened to she put me on the line with a consultant at the call center when I got to the phone the consultant pretended she couldn’t hear me and dropped the call, when I told the store manager she said but she had just spoken to her and told her she’s going to put me on the line, the store staff was very pleasant to deal with but I was left with no groceries and had to unpack my shopping bags. I’ve called the call center a number of times this week but no one is gettin back to me or has an answer for me