My villagers just disappeared

Basically, I had a realm, but I couldn’t pay anymore, so I made it a World, a personal world, I had a Trading hall perfectly lighted, nothing could come in, one day, half of the villagers just disappeared, then the other half as well. I got two more but this time I put it in my base, which is perfectly lighted as well since the roof is made out of shroomlight, and it’s underground with a piston door, and my cleric just disappeared a few minutes ago.

Please fix this, I lost a mending villager because of this. Oh and also iOS still crashes a lot.