Worst experience ever!!

I have a topup 200 cotract with a Samsung Galaxy S9. My contract term ended in March 2021 already, but every month they continue to deduct R246.99 from my account. I have phoned numerous times and every time they say they will look into the issue. I eventually spoke to Devisthree on the 18th of May 2021 who told me the contract has been cancelled as of March 2021 and that all the money that was deducted from my account since then, would be refunded. I just reviewed my statement and there was R615.99 deducted from my account instead of R246.99 on the 1st of April 2021. This is unacceptable! Please cancel my contract, refund my money and remove my details from your data base as I will never take out another contract with Vodacom ever again!