Vodacom **********ly KEEPS billing accounts

Vodacom **********ly billed my mom for months for data contracts loaded on her account without her consent. It was found that she was in favour after a two month investigation and the extra money deducted from her account needed to be refunded to her bank account. After numerous lengthy calls to Vodacom, we today discovered that the amount due to her was credited into her Vodacom account and not refunded to her bank account. BUT they are still billing her for the data contracts that was cancelled and what the whole issue is about??????? After the last few calls to Vodacom a consultant promised me that a manager or team leader will call back to assist and NO ONE IS GETTING BACK TO US!!!!