Proximity sensor isn't working

Hey everyone, when I am in a call and I take my phone away from my face, it takes a good 5 seconds for the screen to come on. I downloaded an app to read the sensors, and when I uncover the sensor, it stays at 0.00 cm. I've already tried getting the Verizon Hidden Menu back to see if I can calibrate it, but I always get the following error when running the `am` command:

Code:

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Starting: Intent { act=android.intent.action.MAIN cmp=com.lg.hiddenmenu/.HiddenMenu }
Error type 3
Error: Activity class {com.lge.hiddenmenu/com.lge.hiddenmenu.HiddenMenu} does not exist.

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Are there any other ways of calibrating it?