Still waiting for feedback

I bought a cell phone on 31/10/15 and on the 05/11/15 the on/off button was no longer working and I immediately returned the it to the store, since it was within 7 days, it was going to be exchanged as per their warranty, but the manager said it needs to be sent back to MTN for them to inspect it, and only then they can exchange it. He assured me that it takes 48 hours for them to collect it. From the 5th till today I a still waiting.<br> I contacted customer service and they too said my matter will be attended to in 24 hours, that was just a lie! Now, I am going to pay for cell phone that I am not using? When is someone going to tell me something? I keep going to the store asking how far they are, the phone is still in the store, no one knows when MTN is going to collect it, I do not have a phone and expected to pay for it by the end of the month, this is utterly unfair!