Can't add 'Orb of Storms' to my combat tray

Hi,
Can't add Orb of Storms to my combat tray. I have the required intelligence skill level. There are no support gems loaded, so no additional requirements need to be met.
Orb of storms requires level 6 and 16 INT. I'm a level 13 sorceress with 45 INT.

In the skills manager, Orb of Storms is visible and I can add/remove it but the tool tip fails to load data when clicked and there is no DPS calculation tip either.

I can send a screen shot if anyone know how to add to this thread.