Arduino nano 33 iot / Firebase / connection refused


With Arduino nano 33 iot, I use this library to connect to firebase:

It could be simple and right away but not, I have in the serial monitor an error from the first firebase connection:
----------Can't set data--------
REASON: connection refused

Yes, I put the FIREBASE_AUTH (which is deprecated in Firebase but everybody uses it)

Do you have any ideas?

ok actually just a problem in the FIREBASE_HOST: this must be set withoutthe "https://" nor the final "/"

problem solved