After I have boot my Win10 computer the tray shows a red cross near the security (shield) symbol with the hint "action required". After opening the security-center it takes some time before the following errormessage (in Dutch) is shown saying that the F-Secure service has stopped and a button to restart it. It helps a while setting Defender as a periodic scanner but after booting four, five times the problem has returned.
I am also only an F-Secure user (their home solutions) and noted trouble(?) is also known for me.
At least, I often receive notification from Windows Security Center after boot up Windows 10. My experience is about temporary state (status, usually, switched to good after some minutes automatically).
In addition, F-Secure own main user interface with good state.
My experience is about beta F-Secure SAFE solution (FS Protection) - so, I reported this experience via beta portal channel (and tried to discuss there).
Maybe, it is possible to report your experience via their official F-Secure Support Channels (chat as example):