Can't allocate Watcher's Eye Prismatic Jewel

I just got this jewel

"

but I can't allocate it into my tree and I don't know why. It is the only jewel of that type that I have. When I try to click on the jewel socket it just doesn't allocate, it is like if my click doesn't work.

Any help?

Please close this thread, I just didn't notice that I had the same jewell allocated already.