Weird problem when refreshing a database entry

Hi,
I am using a MariaDB server running on Debian and several Kodis (3 Android, 2 Windows) sharing the same database. Thumbnails are stores either locally or in an SMB share. All were version 19 until a couple of days ago. Android kodis worked with some minor problems, sharing the databases OK (I had problems withe the Windows versions, but this should be for other thread..).
I upgraded both Android units to V.21. I am not using the Windows versions (I am in the process of upgrading to v.21 one of them right now, to see if I can reproduce the problem).
The DB server was MariaDB 10.3. I decided to do a clean database for the new kodi so I followed the procedure to reset the databases before launching any v.21. Then I started fresh and scanned one by one the folders with movies. I have an Action folder, for example. Se it as Movies, using the default scrapper (TMDB python) and waited for some time until the scan process finished. Then I looked to the movies as the scrapper recognized them. There were some mistakes, which I always correct using the Refresh button. I tried to do the same, but instead of showing the movie name as recognized (which was the case until now) the Refresh button looked for Action, the parent folder.
I changed the server by MariaDB 10.5, now a fresh installation in a different computer. Same drill, same result.
Anyone had the same problem?