Rude store manager

I walked in at nizams store Eyethu mall orange farm around 12:30 ,today on the 23/06/24 to buy adaptors and light handle adaptors were more than 10 in a box with a price written on that box R18 each when paying I was charged R25 rand when quering that I was told (pay what the computer asks you or live it) that was the store manager who was telling me that