Strange issue after restart of one plus two

I have a One Plus 2. After restarting my phone the following symptoms have occurred: - No alerts/notification pop up on the screen for emails or anything - I can no longer switch between apps using the right button. It just doesn't do anything, and I have to back all the way out of any individual app in order to make it work. What I do know: - the touch screen and all buttons work. For example pressing the right button causes it to vibrate - No app has problems loading As you can imagine this is amazingly frustrating. What could be wrong? Can I fix this without factory reset? I am using Oxygen OS 3.6.1, model number A2005.