I'm running the Tuya plugin to shutdown the printer. It works with the plugins interface button and also with OctoApp unless I use the gcode command which is M80/81 "192.168..." or @TUYAOFF "192.168...".
Then I get an unknown command reply by the Terminal. I did ask in the github repo for help but it seems the creator isn't active any more.
Strangely enough I also installed PSU control to be able to shut the printer down in idle after specific time which does also use the M81 gcode. The PSU plugin got this working. This error was present before PSU control so I don't think the two plugins interfere each other. Anyone can share a light on this issue?