Item paid for not recievd

At the till at Pick a Pay Hyper Montana, I required a price for an Ava tampon menstrual cup before they start ringing my shopping. I've told the lady that I'm not going to take it. She called her supervisor and the supervisor told me that it was cancelled. When I paid, I thought that the few things I've bought could'nt be that expensive and when I got home I saw to my dismay that I did pay for the item after all. I have send Pick a Pay 6 emails and was promised over and over that they will sort the problem out but until now no one contacted us nor has the issue been resolved.