I am dealing with locations right now.
After I created a location, I used "Edit Locations" to create the values for country, location, etc. (see Edit Locations.jpg) and wrote the metadata back.
When I look at the data in the metadata panel, I only see the ISO Country Code (DEU) and Country (Germany). The other fields are empty (see Metadatata.jpg)
I did not find any explanation in IM Help.
The database diagnostics does not show any errors.
In Metadata Analyst I do not find any hints.
What is the reason?
The screen shot shows you editing IMatch locations. This has nothing to do with metadata in files. At least not directly.
See Locations (https://www.photools.com/help/imatch/geo_locations.htm) in the IMatch help to learn about the purpose of locations and how you can use them in Metadata Templates and the Map Panel to assign locations to files, to search for files etc.
To enter location data for images, use the Metadata Panel or Reverse Geocoding (https://www.photools.com/help/imatch/tools_revgeocoding.htm).