Vodacom continues to debit customer's accounts after numerous requests for plan to move to prepaid

I have contacted your retentions department numerous times requesting for my account to be reverted to prepaid so that i can retain my phone number. Once the contract ended my debits still continued without the benefits of the initial contract. Whenever i called in to the retentions department requesting for my line to now be prepaid the advisor always tried to sell me a new contract which i declined each time. I was then reassured that the debits will stop and i will be on a prepaid plan. Yet my bank account was still debited at the end of January. I'm really unhappy and i urge you to listen to all incoming calls to the retentions department. I dont have a contract with you, i haven't had a new handset in years. I just need the debits to stop and for my line to be prepaid and for my number to be retained. I've also been to your Gateway store many times to have this issue resolved