iOS 7 beta 6 a couple weeks ago. If you are a developer who is having this problem, you can fix it by logging onto your developer account and upgrading to the newest iOS 7 beta. If you aren't a developer, it seems your only option is to roll back to iOS 6.It's also possible that the locking is a result of users not updating, because supposedly the problem is mostly happening with those using iOS 7 beta 3. For those of you who haven't been keeping track, Apple released
Of course, iOS 7 is expected to be released in its final form on the same day as the expected iPhone 5S and iPhone 5C announcements on September 10th; so, you have less than two weeks left to go and you can get the proper update, if that is true.