Checkers sunward park bad customer service

Im very angry at a service I got from Checkers in Sunward Park.I went to buy my glossaries on the 26th May 2020.The cashier was so incompitent,she asked if I have a checkers card I said no and asked what is it for but she ddnt have patience to explain and just said its ok if you dont have.Apparently there is a special running but its for customers with that checkers card.When I get home i realised they did not give me the discount on the items on sale I then went back to the shop today to complain and that where they told me i was supposed to get a points card to qualify.