Welcome to the forum, @yorune 
This bug reminds me of this other one:
Could you upload the savefile where it is happening?
To upload a save, locate the folder in
C:\Program Files (x86)\Steam\steamapps\common\Stonehearth\saved_games (assuming a default Steam install), zip the individual save’s folder (not the entire saved_games folder), and upload it. If the *.zip is less than 10 MB, feel free to upload it directly to the Discourse. If larger, please upload it to a cloud storage site like Dropbox, Google Drive, File Dropper, etc. and post the sharing link here.