Avoid going to the store on a Sunday.

I am a loyal customer to PNP Queensburgh but service has really dropped. My complaint is very recent. I was at the store yesterday, yes understably there are renovations being done but pricing on items are incorrect or prices are not visible on the shelves. I picked the items I wanted and proceeded to the till to pay. Cashier scanned the items but then it was system problems and discounts were not deducted. It is a Sunday people have things to do. and not spend time wasted on system issues. I spent about 30 minutes at the till point waiting for things to start working again. while I was at the till the cashier called the manager to assist, the manager had to manually deduct the discounts. She had a pamphlet with her to compare prices and I told her the items that were supposed to be on discount. I even mentioned twice to her, and this line was still not deducted. I saw the pamphlet she had and an item I wanted I had not taken cos I though the prices changed as the price on the shelf was completely different. I spent over R500 so what happens to my smart shopper points as well as the till slip does not reflect. This should not be my problem that there were system issues. Another concern is I heard the cashier say there was also a problem last Sunday. Should I avoid going to PNP on a Sunday so I don't get caught up in another system failure.