FileWatcher lost track of project files (SCSS) Follow

Hey,

I am new to PHPstorm and learning SCSS - everything went fine until an hour ago. Changes could be seen immediately. I don´t know what I did, but File Watcher is now not compiling my scss-files anymore.

If I open a new project, it works fine, but not with that existing one anymore.

If I open the File Watcher Settings with STRG+ALT+S there is nothing listed. If I add an entry and select "Project Files" in the Scope field, it says, that there are "No files in scope" with an orange icon.

Furthermore, my project files now have a yellow background now. According to the preferences, this means, my files are not assigned to that project.

So how can I assign them back?

I am sorry, if this is some kind of beginner question, but I want to understand this programm, instead of just creating a new project so that this does not happen again.

Best Regards
Denis