Pick n Pay review: Smart shopper cash redeemed by teller

I did a purchase and used my smart shopper for the savings. The teller: Domenick Masuku as Pick n Pay Brixton redeemed my smart shopper cash = R40,00. I returned to work and saw I had a slip which is normally only issued for card payments. On closer inspection I realized my cash had been redeemed without my consent. I contacted the manager: Golden and he said he will return my cash from the teller at the store. This is not the first time I have heard of such an instance and it is extremely concerning that the teller can process the transaction without knowledge by the customer.