By doing this, you will need to switch to a personal profile as only the admin who did the connection can remove it.
Tap this link and remove the apps.
Step 1: Click your profile picture in the top right of Facebook.
Step 2: Select Settings and privacy, then click Settings.
Step 3: Click Business integrations in the left-hand side menu.
Step 4: Go to the app you want to remove, then next to the name of the app, click Remove.