We recently reported that a number of iPhone owners have been facing issues with their iMessage application after updating to iOS 7. The issue affected the sending and receiving of messaging through the app with some messages arriving hours after they were being sent.Apple is said to be aware of the issue and says that it only affects about 10% of the iMessage users. In any case the company promised that the fix is on its way and would likely come in the form of the iOS 7.0.3 update.
iOS 7.0.3 is already known to be undergoing a testing phase at the moment and while it's not known what exactly the update is set to fix with iOS, we hope the iMessages bug will be one of them. No date was given as to when iPhone users can expect to receive this update. Apple's status board still shows no issues with iMessage even though the Cupertino based tech titan has admitted the problem.
While you wait for the update you can try to fix the problem by turning their phone off and on, or by going into the settings, turning off iMessage. To do so, go to Settings > Messages. Next, reset networking settings in Settings > General > Reset. Finally, re-enable iMessage in Settings > Messages.