MTN is committing *****

My mother-in-law has a recurring unauthorised debit order being taken from her account. After 4 months of trying to stop the debit order they finally deducted R4000 from her bank account. She went to the Lichtenburg MTN shop but they refused to assist her and told her they can't help her. She has never had a contract on her name nor has she given anybody her banking details.