I presume you had an exercise with three options to choose from.
In such exercises, the first letter of each option is automatically capitalised by the system -- something which is not appropriate for Klingon. Unfortunately, the code has not been adapted to suit the Klingon course in this respect, and this is something we course contributors have no control over.
Developers have been notified of this problem but I don't know how high up on their list of tasks this item is.
This is point 1c in the list of errors mentioned at https://forum.duolingo.com/comment/26778885 .