Villagers not breeding and not accepting professions.

Villagers are not breeding and not accepting professions. I’ve had this village for about a year and I have never had this problem until now. Unemployed villagers suddenly stopped accepting professions when I put job site blocks down. I’ve given the villagers plenty of carrots and bread and plenty of new beds. The unemployed villagers hold the food in their hands and throw it to each other, but they do not breed. Old villagers that have professions still trade and work normally.