Taking payment after cancelling confirmed

I have requested a sim cancelation:

The following mail sent to me:

Hi Johann, we've received your SIM cancellation request. Please note, cancellation will take place on 01-Jul-2020.

Then after that they still send me the following: ------------------------------------------------------------------------------------- Hi Johann,

With the new month approaching, we thought we’d give you a friendly heads-up that your bill will arrive on 1 July 2020.

If you'd like to double check your expected bill, simply check out your dashboard. You'll also be able to track your invoices here.

Thanks, rain

--------------------------------------------------------------------------------

Even after I requested a cancelation.

You will refund my money..........

Yet again the continue to debit my account.

I demand an explanation for this?

The internet use of this service is terrible that's why I requested a cancelation.