The unbind procedure is below:
▼On the process of Facebook
1) Log in to Facebook (PC version)
2) Select "▼" in the upper right corner
3) Select "Settings"
4) Select 'Application and Website'
5) Check this app from the apps displayed and select 'Delete'
▼On the process of App
1) Take note of your password and transfer ID.
2) Reinstall the app
3) After reinstalling the app, use the transfer ID and PW you wrote down to transfer your account