Ah, I see - you have removed possibly the 2nd only router in the mesh network, the 1st is Homey.
I would suggest - restart Homey, and Zigbee shall stabilize within few hours, however you may want to speed this up and go to the maintenance - Attempt to repair - it will ask you to pair devices again but you don’t have to modify afterwards any of your flows etc.
This might be another issue not related to the one above. Do you have many apps, many other devices, eg. ZWave ? If steps above do not help, you may want to share output of [Homey Pro] overview script (but not required in case you smart home is really small).
Also I would suggest to install Sysinternals app and add two devices - Alerts and HP23 - it might provide additional insights.
