Ethernet connection to main Deco connects to a different network
I recently switched from a cable modem to a 5G Gateway access point (T-Mobile). I have 3 decos that I have connected to the new network I created. That all works fine. But when I connect an ethernet cable from my laptop to the main Deco instead of showing the same network as the Decos it just shows as "network 3" or "network 4". I never had a problem with that with the cable modem/router. But now my wireless printer is on a different network than my laptop and I can't print to it. While I do get internet with the ethernet connection I have no idea where it's coming from. I turned off the 5G Gateway and was still getting internet access via the LAN connection (network 4). I cannot figure out where that other network is coming from or why my ethernet connection doesn't show me it's on the same network. (FYI, the 5G Gateway and my decos are using different network names. When I set up my decos with the cable modem I had to create a new network. Could that be causing this? I don't want to go back through all the set up if this doesn't seem like a problem).
Also, I have my decos set up as routers. Should I be using access point instead? (I tried this on the main deco and it didn't have any effect).