My phone time is off by 10 minutes. How do I correct this?

Go to Settings/General/Date & Time and turn on Set Automatically.

You might want to check to see if your time is on Set Automatically. Just like the above answer stated, go to Settings- General- Date & Time. You can enter the correct time yourself if you turn off Set Automatically and then click on the date/time that pops up. It’ll bring up a calendar and a place to change the time. Hope this helps.