Villager Types and Summoning Tags

I am creating an adventure map that requires a few custom mobs. Currently, I am attempting to create an Armorer Villager with the tags "{Invulnerable:1, PersistenceRequired:1}". I have summoned villagers with these tags, and the tags are functioning properly, but when I add any one tag it only summons certain kinds of villagers, such as the Farmer, Shepherd, Fletcher, and Fisherman. No matter how many times I attempt to summon an Armorer, or any other kind of villager, it does not work. If you have ANY idea on how to fix this please let me know.