Accused of tampering with the product price tag

On Monday 02/04/2018 evening I went to the Dis-Chem pharmacy at Canal walk to purchase Johnson's Vita rich firming body tissue oil, and displayed on the shelf underneath the product was R89.90 so I went to pay. The purchase was done at 20:09, I checked my till slip when I got home around 22:00 like I usually do if I don't check the till slip at the shop or when the teller is scanning the products I'm purchasing I noticed that the product scanned R114.90 and obviously the shops are closed already so I couldn't drive all the way there so I decided to go yesterday 03/04/2018. I got there and when to the front desk next to the door and they said I must go to till number 19. I went to till number 19 and explained my situation the lady who assisted me asked another employee to go to the isle and get the tag from the shelf which she also brought the tag written R89.90, she then went to the manager who told her that he can't give me the product for R89.90 because I came the following day and there was a different manager the previous night unfortunately he can not assist me. I asked the lady to call the manager whose name is (Darren Weaver) a trainee manager, so he came and told me that the tag is incorrect, it does not belong to the product I bought, he told me I should have come yesterday already. I told him I noticed after 10 pm when I got home, maybe he wanted me to take a broom and fly I don't know where to coz the shops were closed already, then he continued and accused me of placing the tag underneath the product which I don't know when I would have done that and why. I had to suffer for an employee's mistake, the one that did not notice that the price tag on the shelve does not belong to the product they are packing.