When the "Validate Periods" button is pressed, an error pops up stating that "The period from XXX for fiscal unit Year is not valid" even when everything looks like it should be correct.
This UI Action will display the error if the Date and Time System Properties are not a proper format in your instance.
To update the properties, follow the steps below.
1. Navigate to System Properties > All Properties
2. In the Name column, search for "glide.sys.time_format" and go to the record
3. Update the value to the out of the box string of "HH:mm:ss"
5. Go back to the list and in the Name column, search for "glide.sys.date_format" and go to the record
6. Update the value to the out of the box string of "yyyy-MM-dd"