unexplained call rate

i activated recurring anytime minutes-50min immediately on my online contract account at 22:00 yesterday on the 08th Nov and i made a phone call at 22:04 which took me 8min before i heard a voice notifying me that my recurring min were exhausted, i called the call centre and i spoke to Thandazile, she said she can only see the last phone call i made before 10pm and that it will take 24hrs before it can update the system but i don't get it how cause she can see the recent activities within 10min of my 50min activation..i just paid R2k to get my MTN contract phone fixed at repair center on Wednesday and today am getting this!! i want the recurring cancelled and i won't pay for that 8min as well, should it happen MTN debit more R510 of my monthly installment, i will defiantly reverse the payment for the first time from my bank!!! NO MORE CONTRACT PHONE WITH MTN