MOST PATHETIC SERVICE PROVIDER EVER!!!!!

05th of May 2015 I received a call from MTN saying that I am due for an upgrade and that they will make my life easy and do it over the telephone. Worst mistake of my life trusting them, if anything it has been an on-going nightmare since then to date. I was told that as a promo they will upgrade my account with 4 months free subscription, I have ref no-however they have yet to credit my account with this, instead they send me repeated billings adding interest more and more so. I have called their call centre a billion times if they do not cut you off they put you on hold endlessly only to transfer you from person to person who eventually cant help you and tells you a supervisor will call you back in 20 min- MTN MUST HAVE GHOST ****** SUPERVISORS to date NO ONE HAS CALLED ME BACK TRYING TO RESOLVE. I even went into MTN STORES and consultants sent emails to HEAD OFFICE as well as SALES and ACCOUNTS- still no response-ABSOLUTELY UNACCEPTABLE AND WORST SERVICE PROVIDER EVER. Repeatedly having my services suspended due to this I had to go into store a billion times only for them to unsuspended my line-I will no longer pay for a service I do not get- MATTER STILL UNRESOLVED! SICKENING!!