How can I update my iPhone

Assuming you have a compatible device, see: Update your iPhone, iPad, or iPod touch - Apple Support

And: If your iPhone, iPad, or iPod touch won't update - Apple Support

If the above Apple articles do not help, please post back with relevant information. 

As you seem to have quickly solved your tech support issue, could you be so kind as to provide the steps you have taken. This would be a great help for other users.

Thanks for the assistance.