Same. This happens to me constantly. Every few days, the canopy module becomes completely unresponsive until I hard reboot it (I don’t want to get a ladder out and disassembly the fan every time, so this involves turning the circuit breaker off and on again).
When the device is unresponsive, it becomes unavailable in Home Assistant, of course, but I also have another switch in the room that is bound directly to the light on the fan, and it is also not able to control the light. The switch itself is about 10 feet, maybe, from the canopy module, and always has excellent connectivity.
This really feels like a problem with the Thread radio in the canopy module crashing or running out of memory or something.
Any updates would be greatly appreciated.