A few weeks ago the screen on my phone suddenly became unresponsive BUT only in the bottom 1/4" or so. So although I could access most functions on the phone, I could not use it to dial out as the dial function was unresponsive. I rebooted the phone and it returned to normal. Yesterday the same thing happened, but this time I cannot sort the problem despite numerous re-boots and even a factory reset. Is this likely to be a screen issue, and if so anyone any thoughts on whether a new digitizer may cure the problem?