Terrible service, just want to cancel the contract

I am baffled by the service received from Vodacom. My contract ends on the 01/09/20 and I am trying to give them notice of cancellation as I do not want it to renew. I've mentioned I'm interested in staying with them. I'm being told I'll be liable for September bill and to call after the 04/08/20 to cancel. Today I've been told if I give notice of cancellation I'll be liable for cancellation fees. Can someone please listen to the customer for gods sake! I am already going through a stressful situation due to Covid-19 and this is the last thing I need. Can someone please contact me as soon as possible. Preferably someone higher.