One of them is in your "Embedded" library and the other is in the "Archicad migratie bibliotheken NL' library.
You may find you have two "FM_types" in one library and a third in the other library (there are 2 duplicates and one original that is not counted as a duplicate).
This object hasn't actually been placed in your model - it is just duplicated in your loaded libraries.
Delete the one (or two) from your embedded library and the error should go away.
There should only be one in your migration library which is the one I would leave.
Barry
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