I went to kfc Letlhabile this morning to place an order after paying for the order upon revieving the order I was told that the promotion ended whilst the is there on their screen

I went to kfc Letlhabile this morning to place an order after paying for the order upon revieving the order I was told that the promotion ended whilst the is there on their screen. The manager Perm Mangangwe was rude towards me and went to remove the promo on the screen. Pathetic service