Bad customer service

I upgraded my contract with Cell C on the 12 March 2021 after being with them since 2009 but for some strange reason they decided to delay the upgrade.After a long struggle, they finally did it March 2021 and they even sent me a copy of the contract.Suprise,suprise i received my monthly statement which contains what we did not agree upon .I called them, I was told that my number is a prepaid. When i explained that i even have a copy of a contract, I was transferred from Customer service -Retention-Contracts-Deliveries-Contract again. I have lost count how many people i have spoken to The service is really, really pathetic.