We totally, TOTALLY understand you wanting to free your Bunz account from your Facebook account and we’re here to help. What you need to do is this:
From the login screen, tap the forgot password link and type in the email address that you use to login to Facebook
Once you receive the password reset email, tap the link to reset and create a new password. (Make sure you are fully logged out of Bunz on your device browser before tapping the reset link)
This will tie that email address to your Bunz account and you will no longer need to login using Facebook, so don’t forget about your new password.