Ghost email messages
My phone has been doing some really strange things since the iOS 7.0.2 update. Recently I've been getting some strange email messages. They are greyed out so I can't open them or delete them. They have the blue dots next to them to indicate new message, but it says
No Sender
No Subject
This message has no content
The date is 12/31/69
Weird? Now I have about 8 of them in my Inbox. They'll go away after several hours, but then reappear again.
What can I do about them?
iPhone 4S, iOS 7.0.2