Hi, I have this 1 list for admin to add new leave types.

Right now I'm doing if an item's status is 'Approved' in the Leave Request list, it will then subtract the leave balance for that particular employee and leave type. For example, ABC applies for a Sick Leave for 2 days and it has been approved by his approvers. ABC's original leave balance for Sick Leave is 4 days so when his application is approved, his new leave balance is 2 days. It creates issues for me to update ABC's leave balance as I can't use the switch to determine which leave type ABC has applied because the admin could be adding new ones. It also creates issues to subtract for each leave type.
How to solve these issues?

This is my previous method to deduct the leave balance and it uses a switch for the leave type.
Thank you.