## TL;DR
Fix this in Greenhouse by acting on the exact problem first: in Greenhouse open the interviewer calendar for the blocked slot, find the stale tentative hold or all day event marked as busy that overlaps it, set that hold to free or delete it, then force a calendar resync and confirm the slot now shows as open in the scheduling view. Do not rerun the whole workflow unchanged, because the same inputs produce the same failure. Prove the fix on one candidate first, then rerun the full scope and reconcile the results.

```text
Greenhouse scheduling error interviewer calendar shows busy for open slot
```

## Use this when
- The operation in Greenhouse fails with this exact problem: Greenhouse scheduling error interviewer calendar shows busy for open slot.
- The same failure repeats on retry with unchanged inputs.
- An interview, a panel booking or a candidate confirmation is blocked until this is resolved.

## Not for this skill when
- The notice is a platform outage from the vendor. Resolve that first, then return here if this problem remains.
- The interview completes and you only disagree with a hiring decision such as advancing a candidate. That is a hiring call, not this failure.

## Steps
1. Reproduce the failure on one named candidate in Greenhouse and record the full problem text plus the candidate, requisition or panel involved. Verify: the failure is reproduced on demand on a named scope, not only seen in a log.
2. Apply the specific fix for this problem: in Greenhouse open the interviewer calendar for the blocked slot, find the stale tentative hold or all day event marked as busy that overlaps it, set that hold to free or delete it, then force a calendar resync and confirm the slot now shows as open in the scheduling view. Verify: the single failing candidate now behaves as the fix predicts, or the corrected value is visible on the record.
3. Check neighbouring candidates, panels or requisitions that share the same automation, template or calendar sync, because this class of failure rarely affects only one candidate. Verify: the neighbouring items are listed and each is marked affected or clear.
4. Rerun the original operation in Greenhouse on the previously failing scope, watching for the same problem rather than assuming success from a quiet log. Verify: the operation completes and the original problem does not appear.
5. Compare the result against the source of truth, the ATS candidate record, the interviewer calendars or the booked calendar event, so a silent partial success is caught. Verify: values match the source or every difference is named and explained.
6. Record the fix, the triggering input and the verification result on the candidate record so the next occurrence is recognised immediately. Verify: the record names the problem, the fix applied and the evidence of success.

## Variant phrasings

### Greenhouse scheduling error interviewer calendar shows busy for open slot
The verbatim form searchers paste from the console, report or run log. Treat it identically: same fix, same single candidate proof, then the full rerun.

### How to fix - Greenhouse scheduling error interviewer calendar shows busy for open slot
The how to phrasing for the same failure in Greenhouse. The steps above apply unchanged; start at the reproduction step rather than skipping to the rerun.

### Greenhouse troubleshooting for this failure
The symptom first phrasing used when the console hides the full problem. Surface the full problem first, confirm it matches the text block above, then follow the steps.

## Why it happens
Greenhouse reads busy and free status from the connected calendar, so a stale tentative hold or an all day event marked busy blocks the slot even when the interviewer is actually available at that time.

## Edge cases
- The candidate was rescheduled, the panel was substituted or a timezone changed after the failing run started. Refresh the candidate state and reapply the fix against the current values, not the values from the failed run.
- The single candidate proof passes but the full rerun still fails on other candidates. Treat each remaining failure as its own scope, because a shared automation can hide more than one cause.
- The source systems disagree on the correct value. The ATS candidate record governs stage and panel assignment, the interviewer calendars govern availability, and the booked calendar event governs the interview time; record which source won and why.

Compatibility: Greenhouse at current versions, plus the ATS, calendar or video platform the query names; no extra tooling beyond access to the source records needed to verify results.

## Provenance

Resolved from the public thread: https://vectle.com/posts/pst_gj5xZXxiQPq2jruv5-RH4A