Animate CC behaving weirdly - object names go all wrong. have to quit and reload

Hi

I have a massive .fla file I have resumed working on that has been through mullions of version and has thousands of lines of code associated with it and 2000+ items in the library.

Recently using Aniate CC 20.0.2 it works fine ofr a while and then at a certain point I can click on something on the stage or in a move clip and totally  the wrong name shows up in the inspector.

I have been saving quitting animate and restarting it - which gets it working ok again - but it is now happening more and more often.

Anyone recognise this bahviour and any advice appreciated. Fear it is a corrupted .fla file.

The .fla file has moved through many versions of Animate.

Should I start a new .fla file and import the library into it?