I’m not sure exactly what you are seeing that’s wrong, but…
The first thing to always try is to Quit FCP, Restart the Mac, Open your FCP project and try again.
Next:
THE FOLLOWING COMES FROM THE KEN STONE WEBSITE:
“Over 5,000 years ago Confucius wrote: ‘If you are toiling away, you have changed nothing and FCP heads South on you, [starts behaving in strange ways] then it is time to trash your FCP Preferences.’ ”
Click the following link for instructions.
https://www.kenstone.net/fcp_homepage/trashing_fcp_prefs.html
A great way to do this is to use “FCP Rescue” a free Apple Script that will Trash the Preferences for you (and restore nearly all of your user settings afterward).
There are versions for FCP (Pro) & FCE (Express) and a new one for FCP 5.
Download these free Apple Scripts at
https://fcprescue.andersholck.com/
or
https://pistolerapost2.com/fcprescue/
This is one FCP tip that has helped in solving hundreds of “odd” problems.