If you've tried to play any PlayStation Network enabled games on your PS Vitaover the last few days, you may have found yourself stuck in a frustrating loop where you sign in, only to be automatically signed out and told to sign in again.
This issue apparently arises from the newly updated Terms of Service, which Sony has issued to prepare the network for the upcoming PlayStation 4 launch. Due to a bug, these new terms cannot be viewed or accepted on the Vita, leaving its users locked out of the network.
Fret not though, as there's a simple solution to work around this problem:

  • Visit the PlayStation website on any browser (including the Vita's own web browser)
  • Click the 'Sign In' option in the top right corner
  • Enter your PSN credentials in the box that appears and sign in
  • You should then be prompted to accept the updated Terms of Service
  • Once accepted, return to your Vita and sign in as normal

We expect this problem will be resolved by Sony in the near future, but for the time being the above method will ensure you continue your online gaming without interruption.

http://www.computerandvideogames.com...loop-bug-help/