iMovie not letting me export videos - Says “This item cannot be shared while it is referencing media on the camera”

iMovie is not letting me export my videos and keeps saying

“iMovie not letting me export videos - Says “This item cannot be shared while it is referencing media on the camera”

however it’s makes no sense since it’s been exported from my SD card to my computer and it works fine on the computer it’s just when I go to put it on iMovie.

On YouTube all the videos said to

Select all edited clips - cut them - delete the media off iMovie - import them again - click paste (so I don’t have to re-edit it. It didn’t work.

And I didn’t turn the computer off or take the SD card out before it had time to finish, I waited until it was all fully uploaded onto my iMac which is what’s even more confusing to me

I’ve spent over 16hrs editing this movie and I have never encountered this before.

At first I thought it was my fault since I never take my SD card out of my computer but then saw that thousands of people have the exact same issue.

Editing videos/movies is my career so it’s a huge part of my life and very important and the video I have edited now needs to get exported so please can anyone help me.