MTN warranty is a ****

The phone still under warranty date. The screen doesn't work, was sent back because of a few scratches on the back. Is because they want to resell the phone. What have the scratches to do with the screen not working? I am cancelling my contract after 20yrs. The warranty is a ****. How can a phone still be pristine, even afterjust a week? It still has NOTHING to do with the screen not working~!!!!! Can't get hold of anyone at MTN. Also, it took them 3 weeks to give this report, so I've been paying for this phone for 2 months now.