Some iPhone users say their phones didn't change at all, while others that the phone moved back an hour instead of springing forward one.
The glitch affected iPhone owners who subscribe for phone service through both AT&T and Verizon.
Apple, based in Cupertino, Calif., could not be reached for comment Sunday.
It isn't the first time the device has had trouble telling time. Some alarms didn't go off on New Year's Day, and other iPhones fumbled the end of daylight-saving time in November.
The Associated Press contributed to this story.