Twitter Push not working

About a week ago I restored my iP5 and since then I can't get twitter push notifications to work at all - whenever I try to switch it on in the app I get an error saying 'Error - Failed to update your push notification settings'. This happens with the latest version of the twitter app, and the previous one, and on both 6.1.4 and also 7b4...

Any ideas or solutions - i'm really struggling without per user notifications...!