Why not just replace the faulty device?

I upgraded online to avoid the inconvenience of standing in a shop (and because the shops never have stock of the device I want). The process was smooth, but the device is faulty. After 2 hours on the phone and being transferred 5 times (or was it 4?) someone helped me. So this is the procedure: A courier is arranged to fetch the faulty device and take it back to the warehouse. After it has been sent back, Vodacom cancels the upgrade, which takes 7-14 days. Only after the upgrade has been cleared can I do the upgrade again and order a new phone. So I have to wait up to 17 working days for this to be resolved. Why not simply send a new device?<br> <br> It turns out that upgrading in a store is much more convenient because if the device is faulty, it's simply replaced then and there. And I have been told by the consultant that I can't simply take the device to a shop and have it replaced there. Why not? I am quite unhappy with this whole situation, but what can I do? I am utterly disgusted in the process. Whoever thought of it should never be allowed to think up a process ever again.