Crafting cannot make skin permenant

Hi,

I have infernal Nasus skin shard. I own nasus and have 3069 orange essence. when i click the skin shard it has 4 options:

• re roll into random -disenchant to orange essence

both of these are available.

-activate 7 day trial -upgrade skin to permanant -1520 orange essence

both of these are blanked out and cannot be selected.

any ideas why i cannot get this skin?

Thanks,