Horrible Service

I recently purchased a phone through my Markhams account, I desperately needed a second phone. When I arrived home I realised the phone didn't accept my sim card, I then put my sim card into my mothers phone and received a bunch of text messages to show it still worked. I left work to go to Markhams to try & resolve the problem, the lady at the counter assisted me the best way she could & asked for help from her colleagues, eventually one colleague attempted to help. He's name is Kabelo they call him KB, he then told me my Sim card was at fault, I told him that wasn't possible because I had used it, then he kept emphasizing. I asked him if I could return the phone because I had no use for it he told me \I Will Not Allow You To Do That"he even said it with attitude"