If you encounter an error that that says “Check Out failed. Original Record already locked” when working with a Flow rule, this is mostly likely the result of the Flow’s “hidden” Rule-File-Binary (R-F-B) rule not being successfully checked in the last time that the Flow rule was checked in. Search for the Flow rule using “old:” as a prefix. You may see multiple “Binary File” rules listed. Click on the most recent version – typically the first in the list. Within the “Actions” menu select “Release Lock”.