Two different villagers share the same trade progress

Also happened to me once, but in a different setup. I built a hand made village, with all 13 villager professions + nitwit + unemployed + baby. All of the employed villagers had all of their trades unlocked, and I noticed that the unemployed wasn't there anymore. I noticed that there were two stone masons with all trades unlocked, even though I never even placed a second stonecutter. I have no clue of how to reproduce this.

A little while ago I experienced what I think is the same bug. It happened in my single player survival world after I opened it in 1.11. There are several anomalies that could all be connected by a theory of the game confusing one villager's data with another. Possibly, one part of the code may be seeing villagers in a different order, or seeing fewer or more villagers than another, and therefore updating a wrong villager.

I spent several hours in an old village trying to give beds and job sites to converted villagers in a way that would keep them from wandering very far and not being able to find one or the other easily. Note that in this village, unlike any of the 12 others in this world, all but one of the 7 villagers it used to contain became unemployed; only a farmer had a profession. There was initially interference from a villager breeder and a trading hall that used to be out of detection range, but I discovered those villagers were grabbing my bed and blocks so I killed them all off and started over. I also had to kill off all the cats because of MCPE-44299.

I was finally making progress by placing a bunch of beds in a small area, waiting for them to sleep, and then placing a job site block nearby. The villager who claimed it would change to the corresponding profession and jump out of their bed for a moment, which told me which bed went with which job site block, so then I could break both blocks and re-place them where I wanted that villager to live. From time to time I would need to go back to my base through a nether portal I keep locked up behind an iron door. Suddenly, after I'd gotten five or six of the unemployed villagers squared away, I came back through the portal to find that I suddenly had two additional baby villagers in bed while the former unemployed occupants of those beds no longer had a bed. When I tried to accommodate this by adding two more beds, the next day they spawned another baby instead, and one of the unemployed was still bedless.

I now had 10 villagers instead of the original 7. After the babies grew up I decided to make one of the extra villagers a shepherd, so I crafted the first loom block I've ever made (this will be important later) and gave it a home with a bed and the loom. I grew tired and decided to stop for the night, so I headed for my nether portal. After going through the iron door, I discovered the shepherd right behind me, and before I could shoo it out it went through the portal...and then jumped in a minecart for a merry chase. It took me almost an hour to get it home again, and then I was really tired so I saved and went to bed.

Today when I loaded the world, I discovered the shepherd had no bed. In checking my villager inventory I discovered that I now had 11 villagers, two of which were shepherds...despite the fact that I've only ever crafted one loom in this world and it had already been claimed. After another trip or two through the nether, 4 of those villagers simply didn't exist any more. (I verified that with /testfor @e[type=villager_v2,r=90].) And then 3 more babies showed up in the next few minutes, although I never saw any of the villagers mating.

In summary, I sometimes have villagers randomly disappearing. (They weren't killed: The entire village is surrounded by a wooden fence, with extra double-height fences at elevation changes. Nothing can get in or out, and there aren't even any gates in it. It's also fully lit up; I haven't seen anything spawn inside the fence except babies and passive mobs.) I also have villagers either copying other villagers' skins or doubling up on job site blocks (though I don't think it's the latter, based on the one's behavior). It may be unique to villages in which converted villagers become unemployed, and/or it may be related to switching dimensions in this single player world.

The lead up to these problems is long and complex, and it involves game mechanics that aren't very well understood by players yet, so it's probably hopeless to find a way to reproduce it reliably.

Note: Disappearing/despawning villagers was also reported in MCPE-44351, but I'm not confident that the causes of these two reports are related.

This is fascinating. It sounds like you might have had 2 different villager entities sharing the same entity id, a client-server disagreement or a chunk vs. world-village/portal-data disagreement that resulting in duplicating a villager entity. I think it should be considered as related to MCPE-21416 because it an inverse of that bug and could be caused by a similar process.

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Cleaning up old tickets: This ticket had been set to 'Awaiting Response', but has not received a response from the reporter (~3 months+) so is being closed as Incomplete. If you feel this is still a valid issue then please comment, or create a new ticket following the Issue Guidelines which includes steps to reproduce the problem.

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