Error while connecting to FirebaseDB

The arguments , [com.google.appinventor.components.runtime.HorizontalArrangement@4b310cc], [-1], [-6710887], [64], [12] are the wrong number of arguments for Initialize
Note: You will not see another error reported for 5 seconds.

Any help is appreciated, the URL is valid.

This is the error when I press the button to store stuff into the DB.

mmm, are you sure that block is the problem? if you disable/remove the block, the error doesn't appear?

Do you have a procedure named Initialize?

Is your Companion up to date?