App not user friendly and faulty as points vanish.

Went to McDonald's Centurion lake and wanted to redeem my points. The app was taking forever to load and when I selected the items (3x mcflurry)I wanted to redeem it kept buffering and telling me to wait, until I managed to redeem 1 and ended up opting to buy the other 2, however now when I check my point they show that 4x mcflurry were redeemed. Their app is not user friendly, you can only redeem one item per time and by the teller. R75 worth of points gone just like that.