Chosen Solution

My iphones glass was replaced recently , since then the proximity sensor doesn’t work during calls . I tried auto brightness and that works perfectly . It’s only during calls that it doesn’t work . What exactly should I do ?

There are a couple of possibilities here. One is that the proximity sensor was not properly lined up when it was installed within the screen assembly. The other is that it was damaged during this process. Take a look at this guide to see how it is supposed to be installed and if you like, comp[are that with what you have in your phone.