Telkom Unlimited All Hours LTE bundles

I bought the Unlimited All Hours 10mbps 31 days - R629. With 11 days left on this offer now I get messages from Telkom that there is only 6300 MB left.

How does Unlimited All Hours 10mbps 31 days work, when receiving these kinds of reminders? Because reminders like this means that it is capped and then should not be advertised as "unlimited"