UNrealHeaderTool failed for target.... how to fix?

Hi.
I am no good with english so I will ask as simple as i can.

I made new class, and i try to add UCLASS(), and add fileName.generated.h Inlcude but there is build error. this is a screen with errors.
Link Screenshot - b91c10ffd7e0152282534dbf49845778 - Gyazo

any idea how to fix it?
pls help