Why doesn't my Nokia 635 have a proximity sensor.?

[Windows Central Question]

My Nokia 635 hasn`t proximity sensor.

Is very difficult to talk on Nokia Lumia 635 because it has not proximity sensor.
Inevitably the screen is touched, and the conversation is cut. Note in this page says: "No, the Nokia Lumia 630, Lumia 635 aren't missing a proximity sensor" but this is not true.
There are any way to lock the screen to speak? Thanks

 

[xandros9]

Re: My Nokia 635 hasn`t proximity sensor.

Yup, the 630's don't have one. They don't have an ambient light sensor either.

I remember hearing that if the top part of the screen is touched, (there's no buttons there) it'll shut off the screen to mimic that effect. How about you get on a test phone call and monkey around with it to see what works for you.