Screen goes blank after phone call
When I place a call and press send, the screen then goes black and I can't enter any additional numbers ( phone extensions, etc.). I press on the back Icon, the file icon and the screen - nothing. Then once in a while, the screen will show the phone icon and the options at the bottom, but when I go to press the icon for the number dialer or any other icon, it disappears. Best described as a flash and then goes quickly away. This function seems to happen randomly and not because of something I do. Very frustrating! How can I keep the phone call screen active after I dial a numbver?