Cancellation and Billing

As far as I am aware, DSTV is a month-to-month PREPAID service. I cancelled my DSTV with effect from 28 May 2022 which was my next payment date as advised by the consultant. My services were promptly cancelled on 28 May 2022 yet I was debited for the service. This does not seem right since it is a PREPAID services and I have essentially now paid for JUNE yet I have been disconnected. No one advised that I will still be billed for another month without having the corresponding service! Surely I should now be refunded for this debit order given the fact that my subscription has been cancelled and service has been suspended by DSTV.