My handset model is Yu yureka black Screen goes blank after dialing a number and pressing "Call". (I didnot place it over my ear). The screen comes back when the call is disconnected (by the other person). I cannot disconnect a call or do anything while the call is in progress. I'm finding this issue reported by many in yureka forums, but not in here. Hence creating a new case.
Is the proximity sensor being blocked? It's on the upper part of the phone, alongside the camera.