Get online support
Apologies for the delay in response, @zhaoyang1011.
There was a power interruption in the area yesterday which impacted the NBN network though, it was also resolved the same day after NBN Co replaced some faulty hardware.
I can see that your modem is connected for more than 20hrs now and that you should be able to access the internet.
Should you require further assistance, please don't hesitate to reach out to us again.
You may also check our self help options located here: http://tpg.com.au/support
Cheers!