https://finance.yahoo.com/news/iphone-isnt-ringing-fix-2-162359794.html

To turn off Do Not Disturb on the iPhone 6s, 7 or 8, simply swipe up from the bottom of the screen to pull up the Control Center. If you’ve got an iPhone X, you’ll need to swipe down from the top right corner of the display." data-reactid="18">To turn off Do Not Disturb on the iPhone 6s, 7 or 8, simply swipe up from the bottom of the screen to pull up the Control Center. If you’ve got an iPhone X, you’ll need to swipe down from the top right corner of the display.

If Do Not Disturb is active, the crescent moon icon will be lit up white and the moon icon will look blue. You’ll also see a moon icon in the top right corner of the Home screen. To turn Do Not Disturb off, simply tap the icon and you should see a message at the top of the screen that reads “Do Not Disturb: Off.”" data-reactid="30">If Do Not Disturb is active, the crescent moon icon will be lit up white and the moon icon will look blue. You’ll also see a moon icon in the top right corner of the Home screen. To turn Do Not Disturb off, simply tap the icon and you should see a message at the top of the screen that reads “Do Not Disturb: Off.”