Drag & Drop Screen Recording into iMovie

When a Screen Recording is floating at the bottom-right corner, try dragging & dropping it into the iMovies timeline. I repeat, the iMovies timeline.

For me, on my MacBook Pro (2020), the media occurs on the timeline but a second later it says 'Missing File'.

This file is also no longer available on Finder, so it's gone. Gone forever? That I wish to ask.

Trust me when I say I have recorded videos over 30 minutes long, and I've had to re-do them because neither iMovie nor Finder has them.

Apple, kindly help us with this.