Service, what service?

I am trying to change my contract to prepaid. The contract expired on 11 September 2022. on 9 September 2022. I called and after about 10 minutes was assisted and then told I must pay a R200 cancellation fee or can call again on 12 September 2022. I have called 4 times on 12 September 2022 and spend almost 2 hours on hold. an Agent answered on one of the calls and told me to hold while he loads my profile, 25 minutes on hold later the call cut off. They make it unnecessary difficult to cancel your contract, why cant a person not cancel in writing with an email? I have been an MTN contract customer for nearly 20 years, but had enough of this poor customer service.