I received an unsolicited email from Apple telling me that my Apple ID was changed.
Before the email, my Apple ID was, let's say, 'myself'; after it is 'firstname.lastname@example.org'. After this change I cannot update previously purchased apps on my iPad 2 (iOS 7.0.1). And I cannot see my old purchases in the App Store.
I can still download new apps. And I can see these new apps in my purchases.
I already tried logging out and in again in the App Store.
Does anybody know of a solution to this problem?