CELL C continuing to bill me and still waiting for contact to be cancelled that has already expired!!!!!!!!

On the 16/04/2019, I called Cell C and prior t that I called on the 13/04/2019. My data contract with CELL C expired on the 06/04/2019. This is the first time that CELLC never sent a message to inform that the contract is expiring and obviously this is a marketing strategy not to so you can retain the client. Never the less it was a worse experience ever, after being put through to 3 consultants and being authenticated each time, I still never get my query resolved to cancel the contract that expired. I was told by the 3rd consultant that an gent will call me to finalise the contract on the same day . Still waiting and its more than 24 hours. Guess you guys dragging your feet to cancel the contact so you can still make me pay over for this month. Please stop ripping us off