It happened me in the snapshot 20w22 and I don't take any screenshot but if someone has the same problem please help me with that.

What happen?

Well, simple, when I organize my villagers...An armorer was working in a lectern or he took the incorrect site job block. It was rare for this version because it happened in previous version like 1.14, 1.15... but in the snapshot 20w22 it happened and 1.16 pre-release 1, too. ... ...