Billed with an estimated reading with a prepaid meter

My mother installed a pre-paid meter a month and a half ago. Only to receive an estimated reading of over R3000.

When she called to query the bill, she was told that it will take 30 days to review the situation and that if nobody calls her back after 30 days, she will have to call again.

How is it possible that you don’t even know that a prepaid meter has been installed at the property. Also how is it possible that with an electronic meter, estimated readings are still taken. That meter is supposed to communicate with Eskom?

I defy someone to call me back to discuss this issue.