Asda complaint: Rude and mistakes

I ent to Asa to collect a prescription,Have been going there 2 Years.Was already given a George Voucher for staff rudeness. I took items to pay at checkout,where you can buy Tabasco. I paid with my card-The girl said it did not go Through -Saying -Its our end-Then i see everyone using cards and do it again. These 2 Girls are not being helpful. It does not go through, I see a Receipt coming out and ask to have it-The Girl gave the other Girl a funny look ,which made me suspicious -. They held it away from me, I begged to look iy and it transpires that they have pushed Cash on a Debit payment, which automatically voids transaction.The Girl said she pushed cash twice but this is constant rudeness I have received.I had to get money out and extract it from a hidden pocket,I did not want to pull that cash out, As the girls are close friends , began a blame game-The girl just stood there ,wouldnt take the money so I pushed a £20 note and as it was so new ,flew without chucking it. The Girl said I threw it at her? I did not. I had been so very polite, but as I said Ive had problems with staff rudeness -When I asked Where the spring Green -I was given reference about Cucumbers I might need. The girl seemed upset but oblivious to my Voided card by a Purposeful action. I am Mask exempt and believe this annoys Staff. I really dont look forward to this Weekly Shop at that point The Pharmacist came over to give me the Right prescription as he had given me the Wrong One? So Iwould have got home again with the wrong Prescription. I am upset that an Ordinary transaction was sabotaged and having to write this. I then informed that the Pharmacist dosnt want me or Some One else. I intended to complain this and see where I can Take it as Ive Done nothing wrong .