@tiya1990 

Hi, thanks for posting question here.

Here are some suggestions for your reference:

1. Power cycle devices:

• Unplug the Deco M5 units and the Deco X50 router from the power source.
• Wait for 30 seconds, then plug the Deco X50 back in first and let it fully boot up (solid blue).
• After the X50 is fully operational, plug in the Deco M5 units one by one

2. Verify that the Cyberpower battery backup is functioning properly and providing stable power.

3.Perform a factory reset on the Deco M5 units and adding to the network using Deco app one by one.

4.try unplugging the Cyberpower Battery and connecting the Deco X50 directly to power to see if the M5 units connect.