Videos not playing or recording and notification sounds also not working

[Mariah1738]

I have a new ONE Plus 3T. When I went to record a video it showed an error and then I went to the gallery to view other videos. And it couldn't at as well. Other apps that have camera and video playing weren't working as well. And all notifications sounds stopped as well. I restarted the phone and the problem was gone. But after a couple of hours the problem came back. I did a factory reset and cleared cache. But still the problem remains. I would really appreciate your help.