To import Myanmar holiday Calendar, you need to download this link first.
After downloading the Myanmar Holiday Calendar,
1. Go to 'Setting'.
2. Click on 'Policy' and choose one of the policies you want to import holiday calendar.
3. Under the leave setting, click on '+ Import File'.
4. Choose the downloaded Myanmar holiday calendar and click on 'Import'.
5. Click on 'Update policy' and 'Confirm'.
Tutorial video for details: