Thanks for the clarification. I am afraid sending the current password is not possible because the user passwords are stored in a hashed form and cannot be decrypted. So the reset password approach is the only option in case of forgotten password.
I believe the steps from my previous post is what you need to implement. The handler of the "Forgot password?" button is where you should call the cloud function to reset the password (step 2).
Please get back to us if you need further assistance with the implementation.