I have added a custom field (checkbox) in signup but after login other fields coming with user_metadata except custom field
You should provide some additional context information about how you configured to Lock to add this additional field and more specifics about where is the field not available. In particular, is the field not available in an ID token,
/userinfo response or it is not even available when viewing the user profile in the dashboard.
If it’s missing just on ID token or user information endpoint then you should provide more information about how the authentication request is being performed.