Unfair treatment and wrong information given to customers by Vodacom employees.

My grandmother took a contact phone and laptop for my younger sister at Vodacom store at Seshego Circle Center in Polokwane, Limpopo. My grandmother asked the lady who was assisting them (Vodacom employee) if its possible to pay cash every month in the store rather than debit order, she responded with a YES its possible and they can pay R150 for debit order cancelation. My grandmother did that. Surprisingly every month when my sister pays cash of R929 they also debited R498(for 9 months). My grandmother was not aware of the debit orders as she wasn't getting smses from the bank till the September debit order of R929 (other months they debited R498)went through. She then called her bank to query the debit orders and went to the branch to go try fix the issue but that's when she learned it was Vodacom. She went to Vodacom in town (Schoeman street) with an affidavit from the Police Station to query the debit orders because to her knowledge there shouldn't be any debit order from Vodacom. She learned that there's no cancelation fee for debit orders. She then asked what was the R150 for, they told her its assurance for upgrading when a contract is due for upgrade. She was told that debit orders will continue because its a contract. She then asked about the walk in payments, their response was that they thought she can afford to pay twice. She asked to see her balance and she was told it doesn't reflect on their systems. She asked that they call Vodacom head offices, they did but the lady she spoke to couldn't give her any solution. Payment agreement was the 26th of every month but Vodacom debited my grandmother's account on the 28th of every month. Thats 2 days after walk in payments. From the 1st debit order it was R498 (plus walk in payment of R929) only now they debited R929 . My grandmother requested that they send her feedback via email but she never received any communication from them.