Though rare, misplaced sections may appear if OneNote for Windows 10 attempts to sync changes to a notebook but can’t find the section file. When that happens, a Misplaced Sections icon appears at the bottom of your Notebooks list.
Misplaced sections remain in a notebook until OneNote discovers the new location of the section, or until the misplaced section is moved or deleted.
To move a misplaced section to another notebook
Tap or click the tab of the misplaced section that you want to move.
Drag the section into the notebook you want.
To delete a misplaced section from your notebook
Tap and hold, or right-click the tab of the section you want to delete, and then choose Delete Section.
Acknowledge the warning message, and then tap Delete Section.
Important: Deleting a section is permanent and can't be undone. If you aren’t sure about that, move the section to another part of your notebook instead of deleting it.