Night hawk m1 2.4gz and Ethernet not working

[6milelogan]

Hi all,
I recently purchased the night hawk m1 router you use as a home network as the only other alternative is satellite which does not meet my needs as I regularly have Airbnb guests stay next door that also rely on our internet.

The router worked perfect with great speeds for a good 3 days up until I plugged it in to an Ethernet cable to extend the WiFi to another off-brand router in a guest house. I was able to get great speeds when connected to the 2nd router while testing it all night. Then the next 2 (now) it all went downhill.

I had the m1 set to dual band but when I came home, I could only get the 5ghz WiFi to work. The 2.4ghz wouldn’t load anything. When I switched from dual band to 2.4 only, the 2.4ghz worked like normal. But no matter what I tried, I couldn’t get them to both work at the same time with the 2.4ghz being the only one to fail to do so.

I’m not very tech savvy so please try to dumb down fixes and suggestions for me. Thank you very much to anyone that can help me!

Edit: I should also add that even when I had the m1 set to “2.4ghz only”, the off-brand router wouldn’t get connection at all while being connected via Ethernet to the m1.