BILLING ME FOR NOTHING !!!!!! HELP

MTN contract (808) and Prepaid (173) Not willing to help me. Had two contract expired July 2015.Which I phoned to cancel in Sept 2015 ( one number terminated and one move to prepaid). I was told I wont be billing end September FALSE because a debit order went through . Phoned again in October and I was told the cancellation wasn't done in September was then told I will billed end October NOT end November since I will be on prepaid . Surprise - 30 November debit order went through for both numbers . I phoned 808 was prompted to punch in contract number and my contract number were not recognised since on prepaid . Then phoned 173 whom couldn't help claiming that this is contract department problem- asked them to send an email to contract department and asked them to call me, they refused and transferred to an invalid number !!!!! REALLY .WHO SHOULD BE HELPING ME THEN !!! ?????/ PLEASE I NEED A REFUND THATS ALL AND OUT OF YOUR NETWORK !!!!!