Contract has ended and cancelled yet Vodacom claims I still owe more!!!!

I spent nearly 30 minutes on the phone to vodacom to cancel my contract that ended on the 8th of August 2022. The lady confirmed with me that I have paid up until the end of August and I will no longer be billed for that number. I now log into the vodacom app and it is saying that on that number I owe R188.00 for line rental. The lady on the phone never mentioned anything about that and I refuse to pay vodacom one more cent on that number as the contract has now ended and I do not owe any money. It is extremely frustrating to try and cancel a contract with vodacom, they just keep trying to sell me something I do not need. I believe if vodacom refuses to clear that amount owing it is considered *****ing and I will take it up with the Ombudsman.