This tool allows you to fix invalid polygon geometry such as self-intersections polygon. UTM Geo Map will automatically detect polygons with invalid geometry when it clicked and ask you whether to fix them automatically or not. UTM Geo Map cannot perform any further processing until polygons with this invalid geometry are fixed.
You can see the process in the following video:
Module to use: Area/Distance
Module Icon:

Steps: Open Area/Distance module > Click on polygon with invalid geometry
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