@David-TP when I was experiencing issues, there was no IPV4 address under More>Internet Connection>IPV4. See my update above, I have managed to figure out how to get things up and running again.

My Deco XE75 Pro has been working flawlessly for several months. Today it dropped its intenet connection and began displaying a solid red light. Troubleshooting steps taken: - Verified internet modem...