Welcome to the community!
We'd love to help and see what happened on your connection. We tried to check the website and it works fine.
Please post a screenshot of the error message for reference purposes. We tried to use your community details, but no match.
Feel free to PM me your account details (Username/Customer ID together with the address on file)
In case you need a reference:
Have you tried to access the page using your mobile data? If it's the same issue you need to raise this to website host/support.
I am getting this on NBN too. ON windows 10 computer and my phone when on wifi