Sony Experia Z3 Cracked Screen

Good day<br> <br> My husband's got a sony experia Z3 Compact Cell Phone. We upgrade on our phones in March 2015. In May 2015 my husband had his phone in his pocket and when he took the phone out to check a message we saw the screen cracked. I took the phone to Mtn in Welkom and at first we were told that we must send the phone on out own expense to Sony then after about two months of going in and out to Mtn, the MTN in the Goldfields mall send the phone to the repair shop in Bloemfontein. After 7 weeks we havnt heard anything form MTN, i decided to phone them, then i was told that the phone is uneconomical to repair and we need to pay for the strip and assess and the phone will be returned. I phoned sony and they gave me the contact details for SSS Cellular and they said the phone must be sent to them to be checked. I requested this with Nozipho Mpungose and i was told that there is physical damage to the phone. The phone is still under warranty and i feel that the phone must be sent to Sony to be assessed by them. I would gladly accept this if my husband did drop the phone, but that was not the case. i would appreciate any assistance in this matter please.