Share your experience!
Hi, since I have my phone, my sensor never worked
when I have a call, in theory be activacted, but not
Does your phone has a protective case, film, glass? if it does, remove it then
settings > about phone > diagnostics > test > test the proximity sensor.

You could repair the phone with PCC and see if that solves the problem
Bridge (for Mac)
Alternatives on How to backup Xperias
Welcome to the community.
You will have to contact your local support team to arrange a repair. You can use the link in my signature to find their contact.