MTN is such a pain

The samsung J1 promotion of 2 cellphones for the price of 1 was purchased. They were due to be delivered within 7 working days. This was on the 20th December 2015. A month and a half later the phones still had not arrived. There was no phone call from MTN to inform us as to what was the hold up. Eventually we went into the branch to try and cancel this contract so that we can purchase them instore. We have been taken from pillar to post being told we need wait for a block on our profile to be removed which will indicate a cancellation and then be able to take the contract instore. Its now 2 and half months and the block still has not been removed and yet the phones still havent arrived. Im not sure who the relevant people to speak to about this are, especially because when you go to the branch nobody seems to know who must deal with this. At this stage, all we want to is to part ways with MTN, knowing that the contract has been cancelled.