Vodacom refusing to cancel cellphone contracts

Good day...I'm so disappointed at vodacom because I have been trying to cancel my contract with them but they are not processing it. Instead they make it on a month to month basis. This contract expired in January 2025. When I call them, they give me a ref number but they don't cancel it and this is not for the first time. I will never have a contract with them again....NEVER.