Missing object: X objects refer to the missing priority Y

Missing object error for Agile board's Card Color is reported by Integrity Check, but such object is not present on the system anymore.

Agile boards Card Colors can contain stale references to other configuration objects that are deleted from the system.

Try to change the Card Color strategy and then change it back, so that Agile can wipe the suggested values for possibly deleted objects and allow you to select only from existing ones.
If the problem persists the stale data must be deleted from the database using a similar SQL script: Afterwards, refresh JIRA’s internal caches for this change to be picked up – you can do that by going to CMJ’s Advanced page and clicking the Clear caches button.
```
DELETE FROM "AO_60DB71_CARDCOLOR" WHERE RAPID_VIEW_ID=<THE AGILE BOARD'S ID> AND VAL=<THE ERRONEOUS VALUE>
```