MTN AFTER SALES SERVICE

Recently my i phone started getting really hot. I was just a month short of an upgrade so decided to upgrade & pay a small penalty to sign a new contract & get a new phone. On the 4th of June I collected an i phone 7 . For the first 10 days or so I was very happy with my phone & then I realized I was needing to charge it frequently - a few days ago i checked the battery @ 11.45pm by 7.30 the next morning it was totally dead without having been used. It is now overheating when I take a call & the battery runs flat from fully charged every night. Also, I have to charge it 2 to 3 times a day. I contacted the MTN shop where I got the phone from thinking that as I has not even had the phone a month they would replace it. Instead I was told I need to hand it in to be checked & sent for repairs or MAYBE replacement & that it would take anything from 2 to 4 weeks which would leave me without a phone for that time. Not happy at all with the after sales service received from MTN. They were very firm that that was the only option & were not interested in the fact that I would be without a phone for almost a month. After sales service is so important & unfortunately I didn’t receive any from MTN at all!!!!!