Terrible Service From Store Level & Head Office

i visited a new Pick n Pay store based in modimolle ,I had sufficient funds on an app called Tuyu ,and on the list of stores for usuage the Pick n Pay store was listed ,so I was in the store and took some items to the till ,when asked for my payment method I told them I would like to use the app ,the first staff member tried but was clueless after 3 attempts ,she then called another staff member while I stood there and people thinking I had no money to pay for my goods ,after the second staff member also failed and 10 minutes had gone by I decided to pay cash

my issue comes in after I reported the matter to Pick n Pay's facebook page and they promised to give me feedback ,after a few messages they informed me they are still working on the issue and now stopped responding to my messages but are reading them ,it is almost two months and still no answers ,so I'm not sure if they are all just *********** or just do not want to assist ,surely someone must know why the store is listed on the app as a merchant yet at store level they cannot help customers