Getting an error while processing payroll for employees who have 0 salary

Summary:

There is an annual leave, which is an accrual plan and this accrual runs every month for all employees and attaches an element which is Annual Leave Accrual.

So, when the employee is having a 0-salary basis and running the payroll, it is showing an error which is the below:

"Error Message: The liability rate Annual Leave Accrual Calculator wasn't populated. Enter a liability rate in the absence module or in the payroll."

But this kind of error does not arise when the employee has salary more than 0.

Please let me know if anyone has any idea on this.