Bad service at Mall @ Reds Mtn

Took my contract phone to Mtn Mall @ reds shop for repairs on 25/11/2017 and they have approve a new phone at repairs. since beginning December they say the phone is out of stock. they cant even tell me when am i going to get the phone or make arrangement to give other phone of the same value. the staff is rude and not assisting. every time i go to check they tell me the repair center is closed and its not their problem. Mnt is debiting the full amount but i don't have the phone. that is unfair and day light *******. i have contract with Mtn and their are breaching it, if i stop paying then i will be black listed.