MTN dishes out Bad Service to clients

I have three lines on my MTN contract, two were already past due in September for upgrade. I contacted MTN and Christopher Estrice was assigned to assist me. We spoke on the 14 September . i informed him on the 17th that as my line was due 01/10/2015, i would like to do all three upgrades together. On the 2nd October 2015, Christopher provided me with list of specials. on the 5th October i rep**** and have since been waiting for him to get back to him. he did tell me he has no stock of the handsets, i told him to please let me know as soon as he gets stock. also he with supervisor agreed to credit and waiver of upgrade fees for two lines and has point blank ignored my mails since regarding my line upgrade. when i phone i cannot get through, his colleagues cannot assist as he has the credit authorised. so what am i to do. pray for Christopher to one day reply my mail even if it is to say, sorry no stock, is there another handset you may be interested in. i know he reads my mails as i have read receipt on my mails. this is really pathetic service. a client for over ten years gets ignored point blank, and no one can assist me