For some reason I am unable to raise levies from any sort of clergy above the bishopric level. I've checked their relations with the Pope via right-clicking on their portrait clicking "Go to character relations" to make sure that they like me more than the Pope but when hovering over their respective levy numbers in the military panel, it says that I'm able to raise 0% due to the vassal being loyal to himself. What does this mean and why am I unable to raise their levies? What's going on here?