Worst Service EVER!!

<p>On the 13/05/16 I took out a contract with MTN at carnival mall, Store Code 0045,on the 23/05/16 I returned the phone as it refused to switch on. I was told the phone was going to be booked in and sent to Midrand MTN service centre. I was given a number to call to receive a collection number so I may receive a new device. A week later I still cannot get a collection number. I have received no help or feedback from the MTN store.They do not answer calls, no matter how many times you try calling,it only rings. I dont understand how busy can the service centre be that they dont EVER take your call?? If you lucky, you might get a response "Sorry Sir, our systems are currently down. Please call back later"</p>