Bad service. Mcdonalds Sandton

Went to the Mcdonald’s Sandton City branch to redeem a voucher and was told that they don’t participate in the app promtions. What’s upsetting is the manner in which the cashier spoke to me in. This was not the first time!! I could clearly hear one of the cashiers say that she’s tired of these app promotions!! You should should consider hiring people who give good customer service. Truly bad experience. Won’t be coming back.