Users of the MerlMovie app have reported encountering an "instance of diagnostic" unexpected error in recent versions, specifically version 9.9.81. Based on available user feedback, this issue appears to prevent the app from working correctly, and some users have described the app as "not working" when this error occurs1.

This kind of error message—"instance of diagnostic"—suggests that the app is displaying a generic or developer-oriented error message rather than a user-friendly one. This typically implies:

- The app encountered an unexpected situation or bug that triggered internal diagnostics.
- Instead of handling the error gracefully, it exposed a technical message meant for debugging.

Recommended Actions:
- Check for updates: Ensure you have the latest version of MerlMovie, as the developers may release fixes quickly.
- Restart the app: Occasionally, force-closing and reopening the app might resolve temporary glitches.
- Contact support: If the error persists, reach out to the app’s support or leave detailed feedback in the App Store to help the developers identify and resolve the bug.
- Wait for an official patch: Given that user reviews as recent as July 2025 mention the error, a fix may soon be released.

There is no indication in the provided results of a user-level workaround beyond these steps, and this appears to be a bug that must be addressed by the app’s developers1.