Cancellation of MTN data contracts

To cancel a data contract with MTN is non exciting. We have been clients with MTN for almost 15 years....My husband took out 2 data contracts, which expired 29 August 2021. I have been battling on the 135 number since 30 August to cancel the 2 data contracts. I hold on for more than 45 minutes for the cancellation department, then they just cut me off. I also send a mail to MTN customercare, but there is also no response, except for the automatic mail. The consultants that send you through to cancellation department, escalated 2 mails already, with promises that an agent will phone us before 10am the following day, still with no phone calls.