Upgrading of Cellphone contracts at MTN

My 2 x Cellular phone contracts were due for upgrading on 01/01/15. Ordered 2 x BB Z30 and were told that all contacts and data will be transferred from old to new devices in-store. Received devices on 31/01/15 - Assistant at MTN Outlet could not transfer any contacts or data and had no flip cover in stock. Went to Vodacom on 02/02/15 to purchase flip cover - was told that BB Z30 has been discontinued. Colleague @ work was also informed by Autopage that BB Z30 has been discontinued when she upgraded. My husband returned both devices on 03/02/2015 - Nathalie v d Bijl signed acceptance of devices but refused to accommodate us with other devices. I am not happy with the devices and do not want to upgrade to devices which have been discontinued - it is my prerogative to return devices within 7 days. For a month I have been phoning MTN and e-mailing them with no luck. I only want the upgrade to be cancelled or devices replaced with other devices. The BB Z30 does not feature in the March 2015 MTN Catalogue which obviously means that is no longer available. I prefer that upgrade be cancelled or devices replaced.