My new Outdoor BE25 (backyard) is connected and working over a POE line back to a Unifi POE 48 port switch where my main Deco BE63 (Upstairs Closet) is also connected to.  The switch is then connected to an ATT BGW320 router/modem with 1Gb Internet.  The BGW320 is configured for IP pass through, so I expect the main BE63 to handle DHCP, etc.  I have three other Deco units W7200 (Garage), BE63 (Toms Office), W7200 (Living Room)  They are all connected to the same 48 port switch.

My problem is that the Outdoor BE25 connects back to the main Deco via wifi, and has weak signal.  I do not understand why it won't connect over the POE Ethernet back to the main Deco router?  Because of the weak backhaul signal, it occasionally drops and/or has poor performance.

I also had tried to use the W7200 (living room) over Ethernet and it too had issues as well, so I just let it connect over wifi back to the main unit.

How can I get the outdoor BE25 to use the ethernet connection instead of wifi back to the main unit?

Thanks
Tom