***** committed on my account

I opened a contract with Mtn for a galaxy note 3 and a tablet in 2013 December at the mall of the North in polokwane.i was paying R808 per month for almost 2 years until last year December.i called the mtn call center to enquire about an upgrade that was due and I spoke to a lady called Langavi Baloyi who said I upgraded in October 2015 somewhere in Joburg.i told her that I haven't been to joburg in a long time (last time was in May 2015 and I was only passing by to get to the Eastern Cape).I also told her that in October I was here in the Eastern Cape working so it cud nt have been me.she then said she can see that ***** has been committed so she will deactivate the account and file a ***** complaint and that I shud email her 2 affidavits for both phones and 2 copies of my ID which I did beginning of Jan 2016.she promised me that they will call me and update me.Then December 31 a debit order of 1450 went off from Mtn.i called to enquire on the 3rd and was told not to worry as it will be returned to me once the investigation is over.i have since been calling and have been given the run around.ive resorted to reversing their debit order monthly so that someone may call me.Help!