Can i catch sign up error in auth0 lock handler?

I want to catch sign up error in my code when using auth0 lock embedded form. For example, error, when i enter credentials of user, which already created and try to sign up. I want to catch this error in code and get some info from there.
I have already set handlers for authorization_error and unrecoverable_error errors, but this handlers don’t fire when error is thrown.

Is it possible to catch it?
And what i need to do with form, to fire authorization_error and unrecoverable_error handlers?