Treated unfairly by Vodacom

I had a contract with Vodacom from 31/ 03/ 2019 which expired 31/03/2021, The last debited order went of on the 01/04/202. To my surprise my vodacom account was credited with 175 airtime and when I call the to enquire about the airtime they told me I was given the airtime because I did not cancel the contract, I called and requested the contract to be cancelled and even send emails for cancellation.but they ignored my request. I called them again and was advice that the contact is cancelled .and I will receive an email confirming the cancellation, and my number will be converted to prepaid, On the 01/04/ 2021 a debit order of 175 went off. vodacom credited me again with a 175 airtime. I called them to reverse their airtime because I do not need it, I even sent them email and they ignored my request. and i did not use their airtime.,on the 02 June my account was debited.again. I reversed the debit order now Vodacom has listed me on the credit bureau even though my contract is paid up..VODACOM STOP FORCING ME TO TAKE YOUR AIRTIME AND REMOVE MY NAME ON THE CREDIT BUREAU MY CONTRACT IS PAID UP !!!!