diff --git a/bazarr/subtitles/processing.py b/bazarr/subtitles/processing.py
index aa423285b..c5345966e 100644
--- a/bazarr/subtitles/processing.py
+++ b/bazarr/subtitles/processing.py
@@ -149,7 +149,7 @@ def process_subtitle(subtitle, media_type, audio_language, path, max_score, is_u
                                   reversed_subtitles_path=reversed_subtitles_path,
                                   hearing_impaired=subtitle.language.hi,
                                   matched=list(subtitle.matches or []),
-                                  not_matched=_get_not_matched(subtitle, media_type))
+                                  not_matched=_get_not_matched(subtitle, media_type)) or [],
 
 
 def _get_not_matched(subtitle, media_type):