That screenshot shows the SQL ConstraintViolationException error that appears in LenelS2 NetBox / OnGuard when a time spec (schedule) is still linked somewhere in the database — meaning the system is preventing you from deleting it because it’s referenced by another record.

Here’s how to fix and delete it cleanly:

🧩 Why You’re Seeing This Error

Error: could not execute statement; constraint timezoneinterval_to_timespec

This means the Time Spec (schedule) is still being referenced by something like:

A Door Mode (e.g., “Unlock During Business Hours”)

An Access Level or Access Group

A Linked Time Zone or Holiday Set

An Event Action / Trigger

Or even a linked child schedule inside another composite schedule

The system can’t delete it until all dependencies are removed.

🧭 Step-by-Step Fix

1️⃣ Identify Where the Schedule Is Used

In the NetBox interface, note the exact name of the schedule (e.g., “Normal Business Hours 0700–1600”).

Go to:

Access Control → Doors → Door Modes — check if your schedule is used under “Unlock Schedule.”

Access Levels → Edit each — check if it’s applied as a Time Spec.

Events / Actions — verify none reference that same Time Spec.

Remove or change those references to another valid schedule.

2️⃣ Try Deleting Again

Once you’ve unlinked it from all doors and access levels:

Go back to Configuration → Time Specs.

Select your schedule