This can happen if the Athletic Group the grade is recorded in does not have a Head Coach selected.

This can be managed by an Athletic Group Manager:
  1. Navigate to onCampus.
  2. Select Group Finder.
  3. Filter the year and athletic group.
  4. Click the Roster tab.
  5. Click Manage.
  6. Set a Head Coach.
  7. Save.
This will then allow the Reviewer to manage/review grades for that group.