Font of Rage - the operation could not be completed

Hello,

I have this issue once i try to put Font of Rage on my Pain Offering skill. There is any solution for that?

I'm having the same issue, try to socket font of rage into pain offering and i get the error "the operation could not be completed"

Edit:

Realized I didn't have enough "Strength support gem capacity" as soon as I swapped a passive from Int to Str, and i gained a slot, it allowed me to craft and socket.