This error is due to duplicated items within a logbook template.
To fix the error, follow the steps below:
Click Access Button
then click HR Admin.
Click the Settings tab, then click Logbook.
Open the Training logbook, then click the pencil icon to edit the duplicated fields.
Click Add, then click Save.
You can rename the items without an X next to them, as they have already been used and cannot be removed unless you delete all the logbooks that have used this item.