For customers experiencing any issues with their NBN service, we recommend the best thing to do first is check if there's an outage on the NBN network.
We have created this article that can guide you on How to Check for NBN Network Outage
If there are no known outages in your area, customers can proceed with the troubleshooting steps indicated on this link : https://www.tpg.com.au/support/nbn-hfc-cable/problems_connect_internet_nbn_hfc
In your case, the service was affected by an unplanned NBN network outage. This has been resolved and your connection should be up and running now.
Thanks but i did check but there was no planned maintenance and it happened on a sunday evening. It is happening again as i compose this message. Not very happy with NBN lately as it seems to be very unstable.
I will ring the support to report this.