iPhone randomly turns screen off, won't turn back on

[Party Sequence]

I know the iPhone screen is supposed to turn off during conversations to save people from accidentally hanging up, but this happens as soon as I make the call, even if I haven't put it to my ear yet. I can't push the speaker phone button fast enough before the screen goes black. And when I'm done with the conversation and take it away from my ear, the screen stays black and I can't hang up the call. Any suggestions as to what might be the problem?

 

[gadgetdad]

Sync and Restore in iTunes, if that doesnt work take it to a Genius.

 

[moneymaster]

I had the same problem. Do you have a case? If so take it off and try, it may be covering the proximity sensors. I have been talking to apple about this problem. They do not know what is the problem. They told me to charge my battery overnight for a few days, uninstall all app store apps, and restore through iTunes, setting it up as a new iPhone. Hopefully that will help.

If not, I suggest taking it to Genius so they can run a diagnostics test on it.