FaceTime problem

Someone kept spamming me and ringing me whilst I was on FaceTime and it ended my FaceTime call and my phone got stuck on the blurry picture of my background. I can swipe off and go to my home screen but can’t click on any apps can only swipe through already opened apps. Anytime I go into FaceTime it gets stuck on this screen and now my lock button isn’t working, I’ve put assistive touch on and it doesn’t lock my phone. It’ll lock if it goes off with auto lock. It won’t lock when I use the button but if I hold it Siri works.

I can’t rest my phone because nothing happens when I hold both buttons. I don’t know what to do