MTN online selling products they dont have stock

I performed an upgrade online on the 22nd of August, and on the 24th I received feedback that it has been approved. A few days later I then called to enquire what was happening and I have been pushed from call centre to call centre, the agents say they dont have the Ilula system and cant check they will ask someone to check but no call backs, I then go to MTN Morningside and get told the package is with DSV. I then call again and get informed no such order exist. After yet another call I am told there is no stock. So why are you selling something you have no stock off. I need that device as I am starting school but not getting any joy