File loading error after upgrade to newer version

Hi to all!
We’ve use nextcloud 14 (14.0.4.2) for sometime. And have no problem.
Some days ago we upgrade it to 18.0.3 and got a strange problem. We cannot view mp4 videofiles from some folders. These files are ok for view. We may download them and upload back (or just copy within nextcloud) and view them successfully. The problem persist within only some folders. The problem is that is there are thounds of files and we wouldnot like to move them another place.
Earlier all of them playied ok.
The error is “error loading filename.mp4”. We tried to rename files within folders but it doesn’t help. Also, we made scan -all for sometimes.

Our configuration:
CentOS 7.5
PHP 7.2.29
5.5.60-MariaDB MariaDB Server