villagers will steal other villagers profession blocks/professions, leaving 2 villagers with the same profession block

so, I was trying to get decent trades so i can get easy emeralds. i had a cartographer, and then a few days later irl, i had  cartographers, and only one cartography table. i hadn't placed another cartography table down however. so i had to make a cartography table and place it down. this has happened many times in the past, but i thought it wasn't a big deal, but now its annoying. sorry for the long post, im not good at summarizing things