Steers Boardwalk Port Elizabeth not accepting Credit Cards

I ordered my goods at the Steers Boardwalk, Port Elizabeth and when I wanted to pay, I gave her my Credit Card. She said that I must pay in cash. I asked her where is the notice that I must pay cash only.

I asked her if I may speak to the Manager, she rep**** she is the Manager. She offered that I may pay with my Credit Card, and I refused.

I want this to be investigated, as why would one only need to pay in cash. We are in 2020, card payments should be allowed everywhere..... unless there is something behind this whole situation.