Hi DesdaZoe,
I feel your pain! A phone that does not light up when you take it away from your ear can be very inconvenient. I have had similar issues with some of my phones and more than once the issue was a screen protector covering the sensor that makes phone light up when pulled away from my ear. Do you have a screen protector on it? Remove it and test.
Additionally, try calibrating the screen: Menu>Settings & Tools>TouchSettings>Calibration. Also, make sure you have the current software version VX11VKV11. You can check by going to Settings & Tools> Phone Info>SW Version. If you have an older version choose software update. If you have the correct software version and issue continues do a factory reset http://is.gd/EnVTouchFR and test.
AntonioC_VZWSupport
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