Poor contract cancellation service

Cancelation process: In March 2020 I phoned Vodacom with my intention to cancel my contract on the expiry date of 17/04/2020. I was told I can only do this in the month it expires. I again phoned them in April after which they told me it has been loaded. Beginning of this month my balance enquiries still showed I'm on a contract and the next deduction is due for end of this month???, so I phoned again on 05 May 2020. This call took another 15 minutes! The operator kept blaming the new vs. old system they're using and that it's slow.

NO CELULAR SERVICE: Finally today 6 May it appears that I'm on prepaid, but now I can't make phone calls, NOT EVEN TO VODACOM. I tried 082 111, 135, 121, none work - "the number does not exist". Yes, I did load airtime. My calls get rerouted to an automated message saying my service has been suspended. I've tried turning my phone off and on again.

PLEASE Vodacom, how hard is it to just cancel a contract on its due expiry date and go on pre-paid using the same number? Now I can't make calls either.