Really a tight lipped question.
But maybe with some daring one might adventure an interpretation. Someone interrupt me if I talk nonsense. It says a method was not found and where it was not found. So, said method is either missing in there where it was not found, or in there is another method that calls that method and doesn't find it at the destination, where it could not be found. I believe that is not a totally devious interpretation.
The best help in that case would be that for self-help, i.e. RTFM.
https://docs.godotengine.org/en/latest/getting_started/step_by_step/signals.html?highlight=signals
hth 😎