When you expand your certificate in the Keychain Utility, is it an iPhone Distribution Certificate? If not, you need to rebuild your certificate. Also make sure that the Application Loader is the most current, non-beta version.
We have recreated everything and now it works.
The problem is that the distribution certificate, maybe last night, was declared invalid by Apple despite the fact that its first status was Active.
We didn't touch anything.
Now the (Folio)app has been posted and we are waiting for approval.