Registration with the OLT failed

If you have access to the modem, take a look into the parental control configuration. It looks like you had a rule configured to block the internet service starting at 7 pm and finished at 8 am in the next day. I told you this because I had some parental rules in my modem and that it is the behavior. 

If it is not the case, so the ISP has to replace the modem because is not working fine, It is not normal that the modem works some hours and after it stops to work.

Hope this information helps.

Regards.

Hello,

Please check the device source. 

1.  If you purchase an ONT of the formal enterprise version

Administrator (installation and maintenance personnel):

Please contact the device supplier.

2.  If you purchase an ONT customized for a formal carrier version

Certain carriers may customize accounts, which are different from the default accounts. For details, contact the corresponding carrier.

3.  It's also possible that someone else changed setting. 

Restore the device to its factory settings. (This operation will cause loss of the original configuration data. Exercise caution when performing this operation.) 

Good luck!

Hello, friend! 

According to the analysis of the problem, the ONT registration failure is caused by the disconnection from the network.

The diagnosis mode is based on the scenario where the network connection is successful.

Please provide feedback on whether the web parameters of the ONT have been modified.

Suggestions for you to try to restore the factory settings first.

If the HG8245H cannot connect to the network, contact the ISP or ONT installation engineers.

Thanks!