Disc-hem staff disrespect over steamer!!!!

Not the cashier and floor supervisor wanting me to prove that the price of the steamer was marked down from R299 to R239 ….I took the last steamer on the isle and the cashier rang it at normal price. When I told her it was marked down she said lets go see the tag on isle. We got there it was already removed . Now I am being asked to prove it was there …. REALLY!!!? I even showed them it was marked down online which they explained can happen that the prices differ. Which os totally fine if the tag was not saying it was also marked down instore… HOW DOES A CUSTOMER PROVE THAT THE WAS A TAG THERE WHEN THEY TOOK THE ITEM AND NOW IT HAS BEEN REMOVED BUT I MUST STILL PROVE IT !!!!