Pathetic service

I have upgraded my cell phone contract online. The device was faulty out of the box. Went to a store to return and get a new device. Store did not help me as I did the upgrade online. The store gave me a number to call that would assist. After calling the number provided by the store, the agent could not assist as I now had to call MTN sales which does not work on weekends and I could only call the Monday. Upon calling the MTN sales number I got a voice message stating that they were closed that day which by the way was a working day. At this point I got worried about my 7 day return policy as time was running out. I called head office where I spoke to 2 people and they eventually put me through to a company called Mondo which is an MTN partner. They assisted me by advising me to return the phone to a store which must then provide me with an IRMS number. The store provided me with the IRMS number as well as a phone number to follow up. Upon calling this follow up number I went through 6 or 7 agents of which none could help. I was eventually put through to an agent at Mondo again which again assisted me. This time I had to wait for the device to arrive at their Warehouse whereafter they would send me an sms providing me with a RMA number. This took 2 weeks. After receiving the RMA number and returning back to the store to get an early upgrade as advised by the Mondo agent, I was told by the store clerk that he was unable to help as the contract had not been reversed yet. I still do not have a new phone and if this continues I will then be paying for a contract with no device.