Nightmare to cancel a contract

I upgraded my phone in Nov 2018, received the phone in Dec, the phone gave me problems where I was advised to take it to the nearest Voda phone shop. The phone came back still not working, I called vodacom again and I was advices to return the phone and they will reverse the upgrade and re enter into a new contract. I received a call from them and adviced me that they have received the package and the upgrade has being reversed. I immediately logged in to order a new phone but the system the respond was I am ellegible to upgrade in 2020 Dec. I called vodacom and I was adviced that I can only cancel the contract in February the 1st. On the first I called again they told me they hv ascalated the query i can only be assisted by the 5.on the 5 they send me an sms informing me that my case has being closed. I called again quess what nothing has happened. How long should I wait for vodacom to do their part. How long does it take for vodacom to resolve their issues