Cannot cancel account, and charge full amount for half the data

I have been attempting to downgrade my account to R200 a month or 20 gig mobile package, or just cancel the package as a whole and go on the top-up basis: Only to find out to today I have R500 which was the previous full amount. 30 Apr 2020 TELKOMMOBI*** -459.00

The package is now listed on the portal: SmartBroadband 20GB Wireless Whereas it was a 40GB package

So now I am being charged the full amount for half the data...

Looking at these sites, to cancel the account: https://www.telkom.co.za/today/media/downloads/Three_easy_ways_to_cancel_online_V2.1.pdf or https://mybroadband.co.za/news/telecoms/284254-how-to-cancel-your-telkom-account.html

Describes accessing the account section under the self-help portal... only there are no accounts listed under this section: "No accounts to display"

So now I am stuck and still being charged, This was last month, I simply want to cancel the service as a whole and reverse the debited amount.

Regards, Werner