Bad service, unnecessarily overcharging customers

So on the 31st of Aug, my mom received an sms stating she needs to pay R350 but she’s on access, fine that was rectified. Now before the end of September she again received another sms stating she needs to pay around R340 and the tv was suspended. When I enquired on fb the person stated the account is in arrears but we paid on time. This is the response by the consultant..

“ Please note that an amount of R 390.23 is due on the account to reconnect the services.

The amount includes R 233.90 outstanding amount on the account and the R156.33 prorated amount for the DStv Access subscription and the reconnection fee.”

I don’t understand how a month to month account can be in arrears.