This is my challenge:

Enforce sharing in Apex
Choose the CRUD/FLS & Sharing app in your Kingdom Management Developer Edition org, navigate to the Sharing Challenge tab, and click the Apex Controller link. Spot and fix any sharing violations.
For this module, you can’t use a standard Developer Edition org or Trailhead Playground. You must sign up for a super-special Kingdom Management DE org. Trust us...it’s worth it.
Click the Apex Controller link in the Sharing Challenge tab of the CRUD/FLS & Sharing app
Modify the class definition to prevent sharing violations

I am getting the error:

Challenge not yet complete in super-special Kingdom Management DE
You have not fixed all of the sharing violations. Don't forget about inner classes!

Please pose the code and guide what to do.
Thanks

This is my challenge:

Enforce sharing in Apex
Choose the CRUD/FLS & Sharing app in your Kingdom Management Developer Edition org, navigate to the Sharing Challenge tab, and click the Apex Controller link. Spot and fix any sharing violations.
For this module, you can’t use a standard Developer Edition org or Trailhead Playground. You must sign up for a super-special Kingdom Management DE org. Trust us...it’s worth it.
Click the Apex Controller link in the Sharing Challenge tab of the CRUD/FLS & Sharing app
Modify the class definition to prevent sharing violations

I am getting the error:

Challenge not yet complete in super-special Kingdom Management DE
You have not fixed all of the sharing violations. Don't forget about inner classes!

Please pose the code and guide what to do.
Thanks