Hoffiric, shocking and unprofessional service

The service I received from the MTN store in Lenasia Signet Terrace was hoffiric, shocking and unprofessional! I went in to upgrade my contract to an S6 edge, which I pre-orded and was second on the list, after waiting 30minutes I was told that they received only one s6 edge and that the first person on the list was the person to receive the s6 edge, however I enquired to see the list to verify that the person who was first on the list had in fact orded an s6 edge, this resulted in the sales personnel becoming very rude and abrupt ! I informed the sales personnel that the MTN head office phoned me yesterday (9/04/2015) and informed me that they had stock but I informed them that I would pick up my phone from the MTN store where I per-orded...whats the point of pre-ordering when they tell you they dont have stock ? it doesnt make sense ? The manager of the store was so rude and unprofessional he took out my application and tore up the application to prove a point to me. This whole traumatic experience raises questions why MTN has such unprofessional people to represent a well-established and global brand ? MTN REQ:***, complained on the MTN website , didnt bother getting back!