I have had this issue on and off a couple times when playing 1.18. I had this issue but less severe in 1.17 bedrock. Every single villager I own disapears seamingly randomly sometimes after saving and quitting. They are villagers made in 1.17 and have a place to live and a bed to sleep in but they all seem to disapear along with all other entities to my knowlege. I have checked and I have the game fully updated, I also have more then enough space for the game and world. I found that for other people that seemed to have my issue but it always claimed to be resolved but this isn't the case.