billing issue

after more than a year, nearly so months, my bill has been R320 max, the nature of my contract. all of a sudden, its up to R 571.16. when i checked my printed bill, there are nummbers not on my cell's list of dialed no's and there are no's on my cell not on the bill, which shows there is a problem, why the sudden escalation. i reported this to 2 'franchises', one phoned back to tell me, MTN said its correct, the other never phoned back.. i have escalated the problem to MTN, i got an 'automated response', to tell me they'll call me with in 5 days, no response. i've posted a message on FACEBOOK, still no response. PLEASE GET ME A TEL NO, and not a 083 no. these they take up to 35 minutes to answer. please, get someone to phone me urgently