Motherboard gone month 13, its my problem

Sony Experia M4 was upgrade end 2014. Motherboard now has apparently gone and Cell C just pull up their shoulders and tell me its my problem.....ITS OUT OF WARRENTY......but io still have almost half of my contrac left!!!<br> VERY VERY BAD service! If it was damadge because of something i did, fine....BUT the MOTHERBOARD has gone!! REALLY.....SONY should replace this phone! I have 5 contract with them, almost 10years loayl customer and this is what i get?????? Anyone else???