Show My Caller ID- setting greyed out and can't be changed
I have an iPhone 4s. All software is up to date but the setting to turn Show My Caller ID is greyed out on OFF and can't be changed.
I have contacted my carrier and it is enabled from their end.I have put my SIM in another 4s and the setting works on that phone.
I have done a full restore and reset all settings with no success.
iPhone 4S, iOS 5