It is possible to support by setting the following items.

Settings > Schedule > Leave Type Settings> Target leave's [Edit]> "Allow negative numbers">

"Disable leave when it reaches 0"

After checking the above items, click the [Save] button to complete the setting.

*Premise: The calculation method for Leave Balance Adjustment  must be "subtract."

After changing the settings, if there are no remaining days left, it will not be possible to apply for acquisition from employees and assign full-time leave patterns or half-leave types by the administrator.

Caution
If the number of remaining days is exceeded before making the above settings, even if there are remaining days at the moment, an error of "insufficient leave remaining" will occur and the data cannot be obtained. To resolve this, eliminate the acquisition of excess days remaining in the past.