need modem/router help

[TightPants]

I have a netgear c6300 modem/router. I just called Comcast a few days ago and had them activate the modem/router. The 2.4ghz and 5ghz both have internet access but direct connection via Ethernet does not. Any idea as to why this may be or how I can fix it?

 

[kanewolf]

Start with a brand new ethernet cable. Verify that it isn't something that simple.