Vodacam is a ******** me

I have cancelled my contract with Vodacom in May 2021 and only in 09 June they sent me a cancellation message for the query ***. on the 1st July they didnt cancel my contract they game me R175.00 TOP-UP airtime and then on the 4th July i called them to ask them to cancell my contract and they said they will. on the 7th July they took their Airtime back. now my problem is im billed R524.00 for what?? as they have took their airtime back. i am not liable for this bill.i would like it to be reversed as i have requested from their consultants.