A bit of a rant… I’m trying to fix my feeble z-wave mesh, which every couple of weeks seems to partially collapse. This time, suddenly a lot of nodes seem to be unreachable, all smart plugs and no battery nodes. Since there is no repair or reconnect option, I have to delete them and add them again as new, losing all energy usage data, and also I’ll have to fix the flows and stuff.
When working in the devtools page, a lot of nodes display as ‘unreachable’ while a simple TEST or toggling them updates the status. So they aren’t unreachable after all, but the tool just doesn’t bother to check or something. Sometimes I also ask for an UPDATE ROUTE because it makes too many unnecessary jumps and can’t reach the outer nodes anymore because of the 4-node limit. After two or three commands on the devtools page, I’ll get the ‘Homey Offline error,’ and it takes a while before I get access again. I can still use the app and all, everything works, but the devtools page thinks my homey is offline. It makes keeping my Z-Wave stuff alive an annoying and time-consuming chore. I really wish the devtools would get a big update, keeping things healthy, detecting problems, weak points, and replacing nodes (Z-Wave or Zigbee); it’s a big hassle.
Okay, I’m done complaining. Going to hug a tree and listen to the birds for a while 
Only this (officially) is a user-only forum. I think you want to send your findings to homey.app/support in case you’d like to get explanations / fixes.
I’m afraid that’s not possible. However, we can write “cheer up, you’re not alone in this” at best 
The “Homey offline” bug seems resistant to any exterminator. Here it mainly only appears when Homey is very busy with “more important stuff” (which appears to be highly classified information).
The “zigbee could not start” bug often got solved by reinstalling the firmware. No factory reset, but just reinstall from scratch. See
https://support.homey.app/hc/en-us/articles/19722884315804-Connect-the-Homey-Energy-Dongle-to-a-PC-or-Mac-with-USB
Maybe Homey falls for the same trick in case of similar z-wave bugs.
