Rude manager and customer rights not followed

I was at pep store morula complex on Friday the 14th October 2022, got something from the shelve which was marked down (red sticker) when i got to the till the lady refused me to buy it saying i put the sticker myself on the item, she then asked the manager Matshidiso who was very rude and removed that sticker and said i must buy with the price that was not even on the tag,i don't know where they found it. Tshidi the manager was very rude and even after i told her that i will report this issue she was so rude and loud for every customer to hear that she is the boss and she refuses me to buy with the price i see. I asked for them to check the cameras to make sure that i am not the one who put that price tag, i found it there but still she refused, rudely so. According to my knowledge the price i see is the price i pay but that wasn't the case.