Proximity sensor not working properly

[sharukh_shaikh7]

Since installing gesture beta my proximity sensor foes not work properly...
I'm using Lumia 520 denim.........
I tried after uninstalling gesture beta but still its not working properly...

 

[srikanth reddy4]

may be a hardware issue.the same happened with my L520 long back.i went to a service center he removed the sreen cleaned the dust in proximity sensor area and it was working