BANK ACCOUNT DEBITED - HAVE NO MTN ACCOUNT

My wife noticed a Debit for R299-34 on her FNB Cheque account with reference: MTN SP A******. Our online bank a/c shows the source as Standard Corp and Merchant Bank and it was a Magtape Debit. I called the listed number 3 times but nobody could provide details - said I must call FNB. I called FNB and eventually managed to get the debit stopped and reversed at a cost of R17-50 to me - BUT - they said I must contact the merchant (who they later confirmed was MTN - on ***) to get the debit cancelled with written confirmation as they could lodge another debit order and if only one digit changed, it would be processed! Ever tried calling MTN? Without a MTN Cell number to punch in you get nowhere. Luckily I requested MTN info and after much badgering got their HO number ***. Called this number at 16:05; again 16;09 and again 16:12. Took forever to answer and each time I was referred to ***** but the phone rang a long time and disconnected. I'm rather desperate - Both MTN and Standard Bank have been mentioned in many Cellphone/Debit Order ***** cases and folks have struggled to get things sorted out - hope this post helps. WE ARE NOT MTN CUSTOMERS!