Accident recording file not saved

I have a Q800 Pro which has been working fine (I thought) until a had a slight accident and after looking at all the saved vid clips I could not find anything to do with my accident.

I know that this should have saved the file in folder evt_rec but all the files in this folder were old. I’ve since been told that I need to delete the files manually because when this folder is full it can’t save any more info and the reason this folder was full was because every time I drove over a bump in the road the cam bleeped and I had to keep changing the sensitivity setting until it stopped bleeping so I didn’t know the folder was full. This needs to be made very clear to everyone about this situation.   

This is completely stupid situation the one time I needed a recording for my insurance company I have nothing.

Why on earth doesn’t the software still save this to the cont_rec and then copy the file to the evt_rec folder so at least I would have still had a copy of my accident in the cont_rec folder.