Go to Leave Setup --> Public Holidays and change to List View.
Click on the "Arrow" icon indicated in the screenshot below and it will populate next year's Public Holidays.
Select the "Pen" icon, found on the right (as shown in the screenshot below).
Scroll down to the bottom and select "SAVE CHANGES".
The system will prompt that "Public holiday was successfully updated".
Once the public holidays for next year has been setup, the staff will be able to apply leave for next year.