No light No LED flash for mail alerts on iPhone 4 for hearing impaired deaf

Brand new iPhone 4 (I don't use the phone for calls so I don't need a later version of the iPhone)

The LED flash was working when I did the first full charge of my phone and set it up for incoming mail alerts.

After the slight update to the iOS, my LED flash stopped working for incoming mail alerts. I've checked the settings, sent test emails from my iMac and did a complete erase and started all over again, three times.

I tested the flash via my camera and the flash does work.

I checked the following settings  (taken from this article: http://howto.cnet.com/8301-11310_39-20122525-285/ios-5-tip-how-to-enable-led-fla sh-alerts/

Settings > General > Accessibility and then scroll down until you see LED Flash for Alerts. Turn the slider to On.

For the LED flash feature to work, you will need to put your phone in silent mode by turning off vibration in Settings > Sounds

Also flip the switch on the side of your phone to turn off the ringer.

Phone is resting screen down and is OFF, which is how it is supposed to be, for this to work. (when face up, the screen will turn on when a new notification arrives).

End of settings.

Any ideas why the flash does not work when there is incoming mail and the iPhone is face down and shut off?