Formula to get Accrual Plan Balance at the end of Plan year

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Hi All,

We have a requirement where we need to rollover leftover balance (after carryover) to a new plan at the end of the year.

For ex, Plan A is an accrual plan. If a person has 17 days of balance at the end of plan year, then 7 days should get carried over to the next year (predefined carryover) and the rest of 10 days should get rolled over to Plan B.

For this, I have written below formula to get the Plan Balance by using GET_PLAN_BALANCE() function. But it is returning zero.

Can anyone please help me understand what is wrong with my code?