Looks like its because you hotreloaded that class. Try closing the editor -> compile from VS and start the editor again.
what is hotreload?
Tried that several times… still no good :\
It’s a thing that lets you modify c++ code and compile it with it taking effect on the game without the need to restart the editor. ( And no comma was given that sentence 
)
Next time if you don’t know anything just go to google and type something like: “unreal engine 4 hot reload”. You will learn a lot faster that way 