Tradfri v1.8.4 not working on Homey firmware 5.0.0.-rc.46

Try to powercycle a couple of the powered Zigbee devices.
After that restart the Homey app for that device.
Just one or to devices

Else try Fixing disconnected Zigbee devices (without having to modify all flows)

After that PtP on Homey [HOW TO] ptp