Open your digi.me app, and navigate to Settings. Tap on the account you want to remove, and from the options press ‘Remove account’. After removing Facebook from your digi.me, the digi.me app will ask Facebook to remove it’s access to your account. Please note that this will remove all of the account’s data from your digi.me library.
You can also do this manually by navigating to Facebook Apps Settings, selecting digi.me then clicking ‘Remove’.