Can’t eject external drives. Can’t add them to spotlight privacy list

I can’t eject any of my 6 external drives. All of them say something is accessing them. Relaunching finder doesn’t work. Logging out and back in doesn’t work. Restarting doesn’t work. In the past when this has happened I have added that drive to the spotlight privacy list and it has fixed the issue but now I get an unknown error when I try to add any drive to the list. I have read and write permissions for the drives. I’m not very comfortable with terminal. What else can I try?