Issue
An employees leave won't calculate. The leave rate is attached to the regular pay code.
Explanation
A leave rate will only calculate when it's attached to a leave type pay code.
Solution
Enter a leave time adjustment to change the leave rate balance to zero. And then, remove the leave rate from the pay code. Now, you can add a leave pay code that uses the leave rate onto the employee pay codes. Now, the leave rate will calculate as expected.