Sherry's iPhone froze up and now she can't boot it up without another crash. So she did a hard reset, which worked. But she's had to hard reset it five times since. Leo says the best thing she can do at this point is erase the iPhone and restore it to the factory defaults. If that doesn't solve the issue, then there's a physical issue.
She should go to Settings > General > Reset > Erase All Content and Settings. This will restore it to the original factory condition. It would be best if she could back it up first. She can do that by connecting it to her computer via iTunes, and do the restore that way. Then it will download the latest OS and install it as well.