I haven't used the DND feature until recently but it stop iMessages from appearing.
How do I fix this?
The phone must be in sleep mode in order for DND to work. Is it?
The mode the phone goes to after it has not been used for a while in order to conserve battery. When in that mode, the screen is dark (off). You can go into sleep mode by toggling the power/lock button.
I thought I could use Do Not Disturb to watch a video uninterrupted.
So is DND just a silent mode? Isn't that what the switch on the side is for?
You cannot. No, the switch on the side is to turn off the ringer. The phone will still vibrate. With DND the phone will not do anything, it will just stay "dark".
Alarms on the clock, however are not affected. They will still ring.
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