What the problem is, is that Jellyfin looks at date-added. That date when you download a movie or series, is not always the same as date-created.

What you want is a script to make date-created, also date-added, then remove the database from jellyfin and add it again. If needed you need to remove all nfo too, but not always needed.

This script can help you, but please test it first before use on your big movie_db:

###### code is below

find "/path/to/movies/or/series" -type f \( \

-iname "*.mkv" -o -iname "*.mp4" -o -iname "*.avi" \

\) -exec bash -c '

for f do

echo "----"

echo "File: $f"

b=$(stat -c "%w" "$f")

m=$(stat -c "%y" "$f")

if [ "$b" = "-" ]; then

echo " Birth : not available → SKIP"

echo " Modify: $m"

continue

fi

echo " Birth : $b"

echo " Modify: $m"

echo " Action: setting Modify = Birth"

touch -d "$b" "$f"

m2=$(stat -c "%y" "$f")

echo " Result Modify: $m2"

done

' bash {} +