HTC One X Touch not working

[Android Question]

My touch screen just the bottom half with the home and arrow buttons are not working. I have to restart the phone to get back to the home page. If I open the home page and access an app I get stuck in that app and can't get back to the home page. This is sudden, it's been working fine for over a year. It did not get wet, it has just stopped working. The rest of the screen seems to work fine. What is wrong with this thing?

 

[Rukbat]

It could be a loose connector or a broken screen (or a broken wire). No way to tell without opening the phone up.