Photos to external hard drive

Hi,

when I go onto my Mac air m1, photos show in library, normally I plug in my hard drive, create a folder and drags new photos to the folder created, now when I do this, pictures show but all show 0kb, never ever had this issue.always the way I do it.

the only way it now works which is annoying, create folder on desktop and drag pictures to there and pictures work and open. Then drag this folder to external hard drive.

any idea why this has done this as never had an issue before, thank you