Bad service

I received a call from Cell C today advising that my contract is up for renewal. I have 2 contracts with CellC. March 2020 this contract was renewed and since that time the Sim card never worked. I meant to go instore to investigate however never got around to it as per lock down. Completely forgot about the contract and after today's call, I got to realize that for 2 years I have been paying for something that I never used. Called the call center and was advised that I need to wait until May 2022 for the contract to end or I need to pay a cancelation fee. I advised the agent that the 1st lady advised that I can cancel the contract cause it is a sim only contract however this agent was adamant that this was the only way to end the contract. I requested to speak to a team leader and was advised that she is on lunch and there is no one senior staff to assist. I found this very strange however after back and front with this agent, she eventually agreed to get the team leader to call me. Haven't received a call. Why is this company still taking money for something that is not used and still be so difficult to assist. Hopefully this will reach someone whom can assist.