Pick n Pay **** and horrible manager

My grandmother was approached by a lady with a card machine at Pick n Pay Waverley. She asked my gran for her Pick n Pay smart shopper card, my gran gave it to her and she yelled "congratulations, you are the second winner today" they told her she won R4562,75. She received an SMS stating she had indeed won the amount. A month later Pick n Pay called her asking her to pay the R4562,75 back as she only opened an account and did never win the amount. Today I went to pay the amount to resolve the issue as it upset my grandmother too much. I was busy telling the manager of Pick n Pay the story as I felt this is not acceptable to **** elderly people like this and we should resolve the issue, he yelled at me in front of all the customers and his employees, I was so humiliated as customers stopped and stared at the situation in front of them. I do not know how Pick n Pay usually handles queries, but I am sure the way the manager of Pick n Pay Waverley handled this today was very *********. I am disgusted in Pick n Pay's gross behaviour.