Have you ever faced this problem after updating to iOS 6 ? Are you sure your Id and password are correct? Here is the solution

Go to settings

As you can see I have an iOS 6 iPod touch You can find this in settings -> general -> about . Then scroll down to find version(open the full image )

Go to iTunes and app stores

Tap your apple ID

Then tap view apple ID

As you can see I live in Saudi Arabia where facetime doesn't work so tap country/region

Tap Change country or region and then pick United States ( first one in drop-down menu )

Change the state and phone to these on top State :LA phone : country code = 044 Number 5555555 As you can see in the screenshot

When this happens, you know that you are going right

Now sign in to facetime and it will sign in Not like before

Now. Chose your email and not your phone number must chose email (this is new to people who had problems signing in) phone number may be there in iPhones but don't tap it just tap your apple email ID

Now you can facetime anyone yuppy

Cathy Murphy you can put the code in its specified bar as you can see ant it'll work just fine this applies only if you have credit in your account