MTN excuses not sufficient

my husband upgraded earlier this year with what i will call the biggest mistake EVER! on the day of choosing a phone we were told that everything external to fault is out responsibility but all software issues is covered by the MTN. well, needles to day, our phones was due a software upgrade which we did. it crashed the phones both and we had to take it to MTN. they said its our fault for not doing it correctly. we shouldnt have done it. okay if it was a feature for specialists why not say that. phones have been going in and out for swipes and reloads of software. certain apps dont work. now they want us to send the phones is for repair. we are being told we should update the phones. how the hell am i suppose to do it if they cant even get it done. now all fingers are being pointed to us. how the hell did we break it? the software is damaged. this upgrade is not even a year old. i hate these phones. its been nothing but trouble since day one! every month we pay for them on time, yet we do not have the benefits that phones have to offer. but we pay for it. i want new phones, this Sony *******, i want Samsungs. hope you can see how super frustrating this is. Regards Lehane Matthysen