Hi.   I have deco mesh in two buildings 300 meters apart connected by a wireless bridge. Red light on main deco m5 in 2nd building.

Building 1: Setup is Starlink router in bypass mode connected to a main deco m5 connected wirelessly to a 2nd m5 and an m4 in the same building. Bridge: Ethernet cable from main M5 to a Ubiquiti nanobeam ac gen2 which is then connected as a wireless bridge to a 2nd nanobeam unit in the 2nd building. Building 2: Another Deco M5 unit connects by ethernet to the 2nd nanobeam. The deco M5 in building 2 is connected wirelessly to a deco m4.

All was working for about 3 weeks. Now the main deco m5 in building 2 has gone red. No visibility on the deco app. Power cycling the m5 and nanobeam in building 2 doesn't do anything. M5 remains red. Resetting the m5 brings it back to ready mode with flashing blue light.  But connecting the Ethernet from the nanobeam crashes the m5 unit back into red light. The m4 unit in building 2 shows red light when the main m5 crashes, and reverts to flashing red when the main unit is unplugged.

I have an extra m5 unit. Substituted that for crashed m5 unit and same thing happened. Internet and deco mesh in building 1 is working with no hiccups. Laptop connected to ubiquiti nanobeam in building 2 is also connected to internet.

 A couple of notes. On initial install, the deco m5 in building 2 could only be installed as a separate LAN with separate name and password from deco mesh LAN in building 1. And in Deco app, devices in building 2 showed as connecting to both building 2 LAN and building 1 LAN.

I need guidance as to what settings to check and things to try.