Have a look here: Display Myopenhab cloud connection status - #10 by mstormi ( I am refering to the post that starts with the question the following then gives an answser )
I’ve also implemented a rule that restarts the cloud binding (or any binding, actually, I pass the name as the trigger string item). That you need executeCommandLine() for and connect to Karaf console.
Did anyone dig deeper in this issue?
I also face it for a week. myOpenHAB connection is lost, the app does not work outside my LAN (myOpenHAB working, but local instance is offline) and Alexa can’t communicate to openHAB (Hub offline). My instance is also displayed offline in myOpenHAB.
Around the time it failed yesterday, I see these log entries
2022-12-27 16:49:19.325 [WARN ] [e.internal.SseItemStatesEventBuilder] - Attempting to send a state update of an item which doesn’t exist: undefined
2022-12-27 18:39:43.232 [INFO ] [io.openhabcloud.internal.CloudClient] - Disconnected from the openHAB Cloud service (UUID = xxx, base URL = http://localhost:8080)
2022-12-27 18:41:40.240 [INFO ] [io.openhabcloud.internal.CloudClient] - Connected to the openHAB Cloud service (UUID = xxx, base URL = http://localhost:8080)
2022-12-27 22:07:35.503 [WARN ] [e.internal.SseItemStatesEventBuilder] - Attempting to send a state update of an item which doesn’t exist: undefined
Restarting the openHAB service solves the problem.