Hello Nikou,
we would need to take a closer look at it. Can you check the following things:
- Do you have identical image names in the three different flights? If you have identical JPG names in these three flights, it could be a reason
- Do you have other JPG images in the three folders, which are some screenshots or come from a different source? Please have only your drone JPG images in the folders and move the other images to a seperate folder
For my understanding is your data currently in three different folders?
Did you already imported one of the folders and do you get your message now importing the second/third flight folder?
You are running the latest official release TBC v.5.81?