It's difficult to explain with words what your problem is and your video is way too short and only shows the symptom of the problem without showing the rest. In general, once the breach lock for an FD mount lens is locked in place, it shouldn't be able to pop out of an adapter. The aperture lever is usually the trickiest part of mounting one.
Have you watched any of the youtube videos on how to use your FD mount adapter? https://www.youtube.com/results?search_query=fd+mount+lens+adapter
In-built "iris" control broken. Ring nearly closed.. Is the unit serviceable?
Need to make some photos or video. If nothing mechanically broken beyond repair - must be easy to fix.
bump
I wonder if RJ has any interest in making this for Sony FZ mount? (Either from F or EF mount)
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