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: 1.16.4
• MineColonies Version: 0.13.557 Alpha
• Structurize Version: 0.13.104 Alpha

Problem description

I'm running a Direwolf20 1.16 v1.3.1 server and a player sent me a screenshot of their courier saying there was a problem with the Worker's AI and requesting that I send the developer team my latest.log file, which I've attached.
latest.log

Notes or related things

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log in a gist: https://gist.github.com/ravenbuilder934/1f046139c19146fdfe8e7b410be2defa
(please put it in a gist next time)

I ran into the same situation on a 1.15.2 server that I run.

latest.log

I got this message on my server, too (1.16.4 / minecolonies 0.13.535 ALPHA / sturctur0.13.104 Alpha).
Additional I was able to trace back the reason, why this issue might happen:

Reproduction steps, as far as I could trace them down

• I created the build request to deconstruct my blacksmith (medievalspruce, lvl 1)
• The builder finished deconstructing the blacksmith
• I'll assume that there were some open request for the blacksmith still preset in time the building was deconstructed

I could see in the latest.log shortly after the exception, that both courier failed near the location where the old controller block of the blacksmith was located.

I will try to verify it tomorrow with the newest version of minecolonies and structurize.

You'll find the latest.log here (taken like 10 Minutes after the exception)
https://gist.github.com/Leginiel/983752f98db382263ea564beee85f377

Same as: #5672