Not able to return tablet

I upgraded one of my accounts at MTN Roberts (WP) to a 2gig Samsung Galaxy Tab A tablet, initially happy with the product but the problem started when I got home in Potchefstroom. The sim card in the tablet keep on coming out and was not recognised by the tablet. Seeing that I got the tab on 10 Dec 15 took the tab to MTN in the Mooiriver Mall, I was informed that they could not assist me because they are from a different franchise from the one in Robertson, they provided me with repair follow up sheet to show that I reported the problem within seven days for exchange. They directed me to a MTN direct store in Klerksdorp. Moses Makaya, store manager informed me that they can't assist me either due to the fact that they are MTN owned and have not got the tab on their system.<br> MTN does not have the ability to assist me!! MTN is owned by franchises and can't deliver a service to clients from out of town. I upgraded at MTN and complained at MTN but none of the stores can help me because the are from FMZ Cellular CC, Cellnetwork and MTN direct, so where must I complain and have my tablet swapped or cancelled if not at a MTN store?<br> No one wants to accept responsibility please assist. <br>