I hadn't opened my Creative Cloud Pro for 10 days. Today I noticed that none of the applications in my plan would open; all have a "download" label.  It’s as if I had never worked with them. My subscription is valid. What could have happened?

check your account, https://account.adobe.com and verify everything is what you expect.

then sign out of the cc desktop app

then exit the cc desktop app and reopen it.  sign in with the same adobe id/pass used to confirm your subscription.

Try resetting the CC App.

To reset the Creative Cloud desktop app, make sure it's in the foreground, then press:

Win: Ctrl + Alt + R

Mac: Cmd + Opt + R

If that doesn't work, try uninstalling and reinstalling the CC App:

https://helpx.adobe.com/creative-cloud/apps/manage-apps/creative-cloud-desktop-app/uninstall-creative-cloud-desktop-app.html