I am currently using Deco X68 but it suddenly lost connection and stayed on red light. The modem I'm using is working, and I can connect to the internet using LAN on my pc. 

I have tried rebooting the network but it's still on red light. I have tried unplugging and replugging the Ethernet cable but also failed. I have also reset the whole connect but it failed too. I have gone to the Deco app --> advanced --> internet connection --> iP4, and there is no IP address shown. I have also tried copying MAC addresses from my pc to the app but it's still not working.

Basically I have tried every troubleshooting method but still failed to connect my Deco to a working modem.  Can anyone help.