Hi LaraG,
Thank you for reaching out to the community. The leave balances on an employee will be reduced if a leave taken is entered on a pay run. You can check the employee leave balances by selecting the employee's profile and select Leave Balances. From there, you'll be able to see the Accrued Units and Taken Units. You can check on the previous pay run as well if leave taken has been entered correctly.
For more information, you can also check this article: Leave - Entering Leave Taken.
Feel free to drop a comment below if you have any other questions.