I have been hosting a worlds on both LAN and realms for about 4 years now since about 2018 of may after the Update Aquatic. This issue has continued to make it hard for me to continue hosting my server with a huge group of people. So this happens both off realms and on realms but certain mobs (mainly a certain group of them) despawn on my base as well as for other players in my hosted worlds whether its on or off a realm. These mobs are: horses, trusted foxes, trusted ocelots, skeleton horses, bees and villagers. This has continually been an issue we've had to deal with since season one (we do an SMP servers off and on realms and I've hosted them since season one or the first one I started with friends) The bees at first started missing so I closed them in and They started getting stuck flying on doors and on flowers as well as under the bee hives. I tried every fix in the book; moving the bee hives to the ground, moving the flowers and nothing worked. Until I watched one of the bees fly straight through the wall of my base and then I just got rid of the hives completely. (The base is a Blackstone and glass made tower and it is completely closed in)(It may be the glass because one time lightning struck the ground straight under the glass hitting multiple of my pets killing them) (parrots, dogs and cats) I just recently started working on my villager tower/farm or whatever and when I brought one of the villagers to my base I got off for the day and one of them disappeared. I don't know if it had a job or not but it was an adult villager. A couple months ago I started to work on my mob farm tower, (I have multiple towers and the bees are in my crop farm and growing farm not mob farm tower) the mob farm tower includes multiple mobs not just horses, skeleton horses, ocelots and foxes. My base is very big so the mobs will go out of view a lot of the time. I don't always go into my mob farm so maybe this is a problem contributor? The mobs are not named with name tags so I'm going to try this but in the past this has not helped either. I bring back horses and they go back missing days later. I don't know what to do and it just makes me mad putting all these hours and work into my world and the work just disappears.