## TL;DR
Find the definition before you recreate anything, because recreating a definition orphans the schedule and the history auditors need. Confirm the tenant, then look for the definition under Access reviews in Microsoft Entra ID with schedule and one-time reviews separated, and check whether it was created through Microsoft Graph with a different display name. Query the definition by its Graph identifier and repair the caller, the scope or the schedule rather than starting over.

```text
review definition not found
```

## Use this when
- A scheduled Entra access review fails to start for a group or application.
- A Graph call returns not found for a review you expected to exist.
- The review history shows past instances but the new instance never appears.

## Not for this skill when
- The review runs but reviewers are wrong. Fix reviewer settings on the definition instead.
- You need a brand new review for a new scope. Create a definition rather than repairing one.

## Steps
1. Confirm the tenant and directory in the Entra admin center match the tenant the automation or Graph app is signed in to, and note both identifiers in the ticket. Verify: the portal tenant and the caller tenant are the same, or the mismatch is the recorded cause.
2. Open Identity governance, then Access reviews, and search definitions by owner and scope, checking both recurring schedules and one-time definitions. Verify: the definition is listed with its scope, or its absence in this tenant is confirmed.
3. Use Microsoft Graph Explorer or a signed-in Graph session to list access review schedule definitions and copy the exact identifier of the matching definition. Verify: a definition identifier is captured from the list response, not typed from memory.
4. Request that single definition by identifier and read its status, scope and created date, comparing the scope group or application with what the review was meant to cover. Verify: the definition returns successfully and any scope drift is named.
5. Check the app registration or managed identity permissions for the caller, confirming it holds the access review read and write roles in this tenant rather than a different one. Verify: the caller identity shows the required role assignments in this tenant.
6. If the definition was deleted, restore the schedule by creating a replacement definition with the same scope, reviewers and recurrence, and document it as a replacement linked to the deleted definition identifier. Verify: the replacement definition exists, has a future next occurrence, and is linked in the change record.
7. Trigger or wait for the next instance, open it as a reviewer, and save a screenshot or export of the instance for the cycle evidence. Verify: an instance is created from the definition and opens without the not found error.

## Why it happens
Entra access reviews separate the schedule definition from each review instance, and both live inside one tenant and directory. Automation created in a test tenant, a definition removed during cleanup, or a caller using a display name where Graph expects an identifier all produce the same not found response. Listing definitions through Graph settles which object actually exists, and the scope and status fields then show whether the repair is a caller fix, a permission fix or a documented replacement.

## Variants and edge cases

### Entra access review schedule did not start
The operations phrasing when no error is surfaced to reviewers. Work the definition lookup first; a missing or disabled definition explains a silent non-start.

### Graph accessReviewScheduleDefinitions returns empty
An empty list in the expected tenant means the caller is in another tenant or lacks role coverage. Switch tenant context before concluding the definition is gone.

### access review definition deleted by cleanup
Cleanup scripts sometimes remove definitions that look unused between cycles. Recreate with identical scope and recurrence and record the replacement for auditors.

Edge cases to check before closing the review cycle:
- Definitions scoped to a deleted group fail in ways that look like a missing definition. Check the scope group still exists.
- Guest reviewer settings do not affect definition lookup. Do not chase external user settings for this error.
- Recurring definitions pause after tenant changes. Check status after any directory migration.

Compatibility: Microsoft Entra ID Identity Governance access reviews, Microsoft Graph v1.0 access review endpoints, Entra admin center.

## Provenance

Resolved from the public thread: https://vectle.com/posts/pst_bscBxJEc1KqeaVYFc2ZmqQ