Check your battery health.
To view your phone’s Battery Health, tapSettings>Battery>Battery Health.
We recommend plugging in your iPhone before you get going the update process.
Jane_Kelly / iStock / Getty Images Plus
If your iPhone powers down during an OS update it can be very hard to get it working again.
Restore the iPhone from a backup while in DFU Mode.
To do this, firstback up your iPhonethrough your system.
Next,put your iPhone into DFU Modeand thenrestore it from the backupyou just made.
Contact Apple for a battery replacement.
If none of the other steps you’ve tried have solved the problem, it’s likely the battery.
It could be that the battery in your iPhone is defective or at the end of its life.
Apple is your best bet for getting help, socontact Apple Support.
Do Not Disturb mode is also a common culprit; check those prefs as well.
First, try turning Wi-Fi off and on again and/orrestart your iPhone.
it’s possible for you to also try resetting your Wi-Fi router.
There are a number of things you could try tofix an iPhone alarm that isn’t working.
If all else fails, you might try restoring the iPhone to factory configs.
First, contact your cell phone service provider and verify there isn’t an outage.
If that’s not the issue, try removing and re-inserting theSIM cardin your phone.
You could also be turningAirplane Modeon accidentally.
