Upgrade gone wrong!

On the 11th of January i upgraded my cellphone contract. the sales person informed me that the device I wanted was currently out of stock. In the mean time he would do the upgrade and I would be informed when stock arrived and i could take delivery of the device. Since then I have been waiting for said device. When I recently followed up on the status of the device I was informed that I had not been upgraded for a device and only my sim was renewed. After speaking to several different departments i was informed that my upgrade had been outsourced to Mondo Mobile. I contacted them and the whole story was repeated to their service agent. they have told me that this query will be investigated and that they I'll get back to me. i was also informed that i would need to take out an additional contract to get a device which is completely unacceptable since I already did my upgrade for a new device. Today I followed up (7 days after my initial query) and found out that the investigations has to go back to MTN before I can receive feedback. It has now been 7 weeks since I did the upgrade and still no information or progress has been made. The service from MTN and their 3rd party (Mondo Mobile) has been terrible to say the least. At this stage I think they are only after sales and not service. I have been **** to, made to wait an u acceptable amount of time and they cant even bother to keep me updated of their progress. disgusting.