iMessage losing Apple ID when iPhone is turned off.
Every time I turn my phone off, iMessage loses my Apple ID and forces me to sign in again, often losing my messages from when my phone was turned off.
Then I have to go back into the iMessage settings and reset my e-mail address to receive messages in addition to my phone number.
Why doesn't it save the Apple ID?
Thank you for the help.
iPhone 5, iOS 6.1, Also using OS X 10.8.2