I've never seen this nor is there much I can do without steps to reproduce it or at least an indication of what your preferences are. Is there any more information you can provide?
Does it work correctly if you press "ignore"? If so perhaps the check could simply be removed...
Ok, so the last time I think I pressed another button instead of "Repeat".
It happened again, and clicking "ignore" goes back to C2. I can press ctrl+s but it doesn't save.
I used "save as project" to a different folder, and then I can save normally again. But my project kept the * near the name. Closing and reopening the project solves this last problem, and I can save normally again