Mtn problem.

Hello i took out a laptop deal at mtn on the 24 of october 2018 and recieved it on the 1st of november due to no longer afford the laptop i took it to an mtn store at carnival mall and they gave me an refrence number to use that whas on the 7 th of november. At that time my modem whats not activated yet. 3 weeks after that when i called to find out about the cancelation they told me the modem whas activated and the contrackt is matured. Ever since then i have been calling every week to find out what is going on and every time they just tell me they will send an email to the supervisors and give me a new refrence numer. I dont know what to do eanymore i must make my 3rd payment on the laptop that i dont own and whait. If they give me feedback there wont be a problem but you dont get eany feedback. I have been with mtn for 6 years now and this is the first time i am not happy.