Welcome to the community!
If you're having issues with 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 you may perform basic troubleshooting, we did an article that you may find helpful see this link below.
In this particular case, we've seen that your service has been connected to our network for 1d 17h 20m. In the event only device(s) connected via Wi-Fi is affected by the issue. We did an article that will help you on how to improve your wireless network at home.
See links below.