To solve that, you need to; Edit the GACCENTRY table and change the STA field from 2 (Final) to 1 (Temporary) for the applicable journal entry.
To do that, Navigate to: Development>>Utilities>>Maintenance>>On Rows
On clicking selection, Sage X3 brings you to the below screen
On selection criterion, type NUM= ‘ZANWL2101UGAND000003’ then click OK.
The system will open the following window. Look for the field marked STA and change it from 2 to 1. That means the journal status will change from Final to temporary.
Now looking at the journal, the status has changed from final to temporary, and now you can go on and open a fiscal year successfully.