What Companion version are you using?
Also, show us your Firebase component or upload an .aia export.
Thank you very much
Did a new version help?
I tried running your project, and it crashed on startup without any error message.
Looking through its Designer, I noticed this component was missing the Bucket, so I added one:
The Project opens okay now at run time.
I also advise adding a FireBase Error event block:
(I would have used a Notifier, but you don't have one, and having a speech error output sounds hilarious.)
P.S. I could not tell from your Firebase component properties where its server is located.
Users outside the US need to use a US-central Firebase server, or else their projects crash at startup.
I am in the US, so I would not notice this.
Thanks to @TimAI2 for the correction:
All users need to use a US-central Firebase server, or else their projects crash at startup.
P.S. I did not see your sketch for the device with the LEDs. It obviously does not know about the Bucket I added.
Post the code, so we can figure out how to get the app and sketch in sync?