Start with a PTP (a reboot is not good enough), then try replacing the power supply (5V, 2A or more) of your Homey if you’re still using the original one.
Using a non original 2A on it have considered a 3A before. Going to try a longer PTP last i did i held it for 10 min. I turned off the apps that i have that use the zigbee protocol. What i have noticed also is that some of the lights start blinking at times when there is more then 5 with power on them. I have about 25 zigbee devices.