I have purchased Nokia Lumia 620 (still under warranty), since then the sensor was not not working while picking calls. I have already visited Nokia Care 8-9 times regarding the same complaint & they have also send my phone to Head office also twice ( for 1 month), but even after getting back my mobile every time the sensor is not working .After that again they said now we have swap the phone so next time there wont be any problem, but again after 2nd day the issue continued .I want my phone to be replaced by Nokia( not swapping). They are not even addressing my issues & giving phone replacement.