Poor service

I went to mr price tshwane mall Mamelodi, to purchase 2 Jean's, to my surprise I paid two different prices for the same product, then mr manager called sebusiso came, his explanation is this, it was a mistake that they put the wrong price on the other Jean, and further he said he is not going to change the other price for us, and that we have a choice to either leave the other Jean, that is more expensive but Because I wanted both of them I paid different prices for the same product, what shocked me the most from this experience was that he the manager sebusiso changed the other price manually, why did he not do the same for other product ***