3602154 - Remaining balance from previous years is not getting calculated when create new time account even if rule is configured

The business requirement is to:

Create annual leave for each year requires calculating the remaining annual leave from previous years

But after execution of Accrual rule, it can be found: 

Accrual Rule Variables.Balance is retrieved as NULL.

(Rule log: Retrieved 'accrualRuleVariables.balance'. Value: 'null'.)

The balance needs to be the sum of remaining annual leave from previous years.

SAP SuccessFactors Employee Central 

Variable, Accrual rule, Time off, Beginning of the rule, Sum , KBA , LOD-SF-EC-TIM-JOB , Time Management in Job Info - Records & Objects , How To