Firebase, DataChanged triggered also when app start

I use Firebase realtime database as a tool to send commands from PC to smartphone
A command is a node like:

COMMMAND: COM = 12345; COL = YELLOW; VAL = ABC

During the activity of the app that receives the commands, everything is fine
When I send a new command from PC to smartphone, the app reacts and executes the sent command
The problem is when I turn on the app
When I turn off and restart the app, the DataChanged event is triggered, even if no command has been sent from the PC
I believe this happens because in the Firebase db the executed commands are not eliminated but remain in memory for debugging purposes
How can I avoid having the DataChanged event every time the app is opened?

Do you have “Persist” ticked ?

No, ‘persist’ is not checked

Is it the same with compiled apk ? (if this happens in companion)

Yes, the same with apk
But i believe it is normal behavior, when App start, the Firebase library search data on db, and if found the event DataChanged is triggered
Am I wrong?

I don’t know, have not used dataChanged in a way that presents this issue.

Maybe someone else knows…