Afrihost billing for service when it was cancelled

I have been a happy customer of Afrihost for years but its with disgust the way a domain renewal cancellation has been dealt with.

I cancelled the domain in question on the 21 September 2019 and received the confirmation of this cancellation via email.

I am now being billed for cancellation and told that the cancellation wasn't completed by myself, the client.

Then please explain to me why and how can you send a domain renewal cancellation email stating it has been cancelled it it hasn't?

I'm not one to move from one company to another, especially after years of hassle free service but this sort of service is not acceptable.