Text dissapearing from file

I am using Windows beta 2.90.15
Upon opening a project, text seems to have disappeared from one or more of the files.
The first time this happened, the word count appeared as 0.
Now I have a file that is empty but shows word count of 1758.
Screen capture attached

This seems to have happened AFTER I tried to open the project on my iPhone with the iOS app and got the Invalid Project error.
Any help will be most appreciated

ios might have done something silly, like change the text to white. Click in the doc, Ctrl+A (selects everything), and highlight it all. If it shows text, then click the text color toggle (A).

Do you back up regularly? If so, go back to the backup immediately prior to the problem’s appearance. WARNING: Scrivener has a bug when trying to open the file through Options (F12) → Backup → Open Backup Folder. Copy the file’s location, navigate to it using File Explorer, and open the backup file. Everything should still be there. If not, try the next backup prior to that.