Facing a problem with leave application. Days of leave miscalculation here

Hello Everyone,
I’m working in IT department in a company. I am using Dolibarr CRM for the company, but facing a problem with leave application. I have given a screenshot, see there in the Days of leave column the leaves are supposed to be 3 + 3 total 6, but it is showing 12. Miscalculation here.

I need help from experts to solve this problem.