I just realised that X3 shows the modifying date instead of the original date (when photo was taken). Also sorting by date ist not correctly working for the same reason. Or maybe something with my pictures is wrong? But the original date is correctly shown in Irfanview, Exiftool as well as Windows Explorer:
https://www.hueser.ch/testordner/ -> each date = 25-07-2021 which is the modifying date
Could you please have a look at this as I mean this was working some time before...
thanks!
Example (first image is the same as shown in screenshot):