I have done so more testing. I added a cobweb for the villagers to stand in so the food does not drop through. I checked their inventories and they should be able to breed. I moved them 20 blocks away from the place I'm storing other villagers and made sure the beds are not claimed by any other villagers. I have attached a screenshot. I'm suspecting this may be an issue with the other villagers being too close, but this was not an issue before the snapshots.
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[media]It is set to True
I had a similar issue where I had two villagers randomly despawn from my breeder.