import file step

[bemu70]

good morning to all, lastly when amounting a fairly large step file, I open it without problems but when I go to save it the window "one or more components have been changed (what not true...) , they must be saved together with this document". I save but when I reopen the assembly all the components are suspended and I cannot reactivate them.. . .
I tried to see on file import settings but nothing to do.
I noticed that this thing also happens to me on assemblies of 4/5 components......
Does anyone know where the mistake might be?
I attach the image
Thank you.