I took a phone out on contract 3 months ago and suddenly the touch screen has completely stopped working. Besides one small superficial scratch on the phone, it is in perfect condition. MTN now refuses to replace the phone because they say, that small scratch voids the warentee. Is that legal? How can one tiny scratch be responsible for the fact that my screen does not work when the phone is literally 3 months old? Please can someone with a little more knowledge assist me??