Villagers with Professions Won't Trade

This only occurs on my realms server, the villagers in my survival world trade normally. The trade window that appears for professional villagers closes immediately after it opens. It doesn't happen with all my villagers but the bug seems to spread. As time goes by, more Master-level villager trade windows close immediately. I have not damaged or done anything to lower my reputation among them. The other player on the server also experiences this. I traveled a long way to another village to see if it happens there as well and it did.