While playing on my Realm, all of the villages in the world broke. The villagers would not link to bed if a bed was broken and put back down. Any villagers that had a job but not traded with would not link to workstation if broken. Unemployed villagers would not link to any new workstations. 

The villagers would not breed, but would pass food between each other. Existing villagers with jobs and bed would continue to trade and pathfind to bed or workstation. If all beds were broken in village, the game would not recognize as a village and could not start a raid with bad omen. 

I found if I started my exact seed on a different PC, mobile device or console, the villages would work find. It was only on the realm it would not work. The temporary fix I found was to download the world to my local pc, reset the realm with a new world then upload to replace the new world on my realm.