Prerequisites

• I am running the latest alpha version of MineColonies and Structurize for my Minecraft version.
• I checked the MineColonies/Structurize wiki and made sure my issue is not covered there.
• I made sure that this issue is not a duplicate of any existing issue.

Context

• Minecraft Version:1.15.2
• MineColonies Version:0.13.394(also happens in 0.13.421)
• Structurize Version:0.13.94
• Related Mods and their Versions:jei 6.0.3.15

Expected behavior

world load normally

Actual behavior

My chickenheader and cowboy always gave AI exceptions.But i didnt take them seriously because i didn't need a large number of milk or chicken.But i quit game by the chickenheader and cowboy(they were close to each other)and workers are "working".Then i cant load world anymore.
By the way,this may happen by the moment after finishing loading world for which you can still see the world by minimize the window while loading the game(as tou know,it was a pause GUI,then game crashed after returning the game).

Steps to reproduce the issue

1. stand by a worker(or maybe building) that always gives out AI exception
2. quit the game
3. load the world
4. see it

Logs

• latest.log: https://gist.github.com/xiaobbl/505473ed023a46c7c015c2c1cea963bd
• crashlog: https://gist.github.com/xiaobbl/dcb1d0e3588b8eefe088d9199fe6310e

Notes

Viewers

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Apparently the building went null out of the blue. This is weird

The worker crashing is your cook assistant and not the worker you've noted

well,i got another information...
my cook was always asking for more and more food(not as #5395,but a request that seems can never been solved).it used to happens to my builder.at that moment i remove the builder's hut,build another one and hire it again.So this time i do this again.it was strange that after i rebuild the resteraurant,i can rehire my cook but my assistant cook seem to be never fired and worked as usual.everything goes well in an hour until i quit the game:(

It seems like something corrupted that assistant cooks data weirdly.

well,so the issue is that the assistant cook cant be fired automatically after remove the restaurant...
now im trying to delete the citizen with NBT tools:(

@Raycoms i wonder if the file uder the save/my_world_name/minecolonies can save my world:(

Fixed in latest (will be on curse in 5 minutes)