Cancellation of contract

I've phone vodacom on 30 november 2020 and on 1 december 2020...but no answer after selecting all the options. On 1 december and 2nd december 2020 I've send several emails...but no reply or phone call. I've asked in the email that my contract must be cancelled because the contract ends on 31 december 2020 for I'm unemployed and won't be able to continue with the contract. The service of the cancellation dept is very very poor. When a person contacts them for renewal or a new contract they are quick to deliver. I hope that the cancellation dept will respond to this complaint