diff --git a/beetsplug/lastgenre/__init__.py b/beetsplug/lastgenre/__init__.py
index 15aafd15b0..d1d659c196 100644
--- a/beetsplug/lastgenre/__init__.py
+++ b/beetsplug/lastgenre/__init__.py
@@ -320,7 +320,9 @@ def _get_genre(self, obj):
                 genres = obj.get("genre", with_album=False).split(separator)
             else:
                 genres = obj.get("genre").split(separator)
-            keep_allowed = set([g for g in genres if self._is_allowed(g)])
+            keep_allowed = deduplicate(
+                [g for g in genres if self._is_allowed(g)]
+            )
             if keep_allowed:
                 return separator.join(keep_allowed), "keep"