Iphone 6s on repairs for 21days

Helllow Peter... My name is Bongekile Mabuya i have a contract with Cell c ,i took an iphone 6s around 11November 2015... It been 79days which is 2months and 17days... Iphone 6s went off around 7:25am in the morning thinking maybe its a battery even though it 41% my battery level at that time..I charged my phone hoping it will show signal that its charging unfortunately no signal.. I sent it back to cell c, i was hoping they will give me an alternative phone to use for they said i must wait for 21days thats too long without a phone... The months are still early for a faulty on my phone.. I cant continue paying for a phone that is already been on repairs for 2years, what if something \another fault again regards to phone \" how will i tackle that again. I have no phone with no internet i had to buy those R100 cheap phones to receive calls.... <br> ?<br> "