If the uploaded episode is identified as a non-existing season and episode on IMDB DB, then these errors can occur.
In your case, IMDB episode ID did not exist as S02E26, but it is showing the S02E26 designation.
"Ben 10: Ultimate Alien" Couples Retreat (2012)Subtitles for high-definition movie
[S02E26] Ben 10 Ultimate Alien S03E14 Couples Retreat
When this occurs, check that episode ID is correct to IMDB reference, then do an IMDB update at the episode level to kick start and update sync. It now shows the correct SxxEyy.
https://www.opensubtitles.org/en/subtit ... retreat-sr
Then, you need to IMDB update at Root or series level the same way. This will reorder any new changes and display.
https://www.opensubtitles.org/en/ssearc ... ovie-57747
Double check, but they should be in agreement now. In the future before uploading, make sure that your episode designations always agree with IMDB before uploading.