Samsung galaxy s5 calling problem

[wolfkillerro]

i have a Samsung Galaxy S5 and when i call someone the screen goes black and i can't close the call if i called the wrong person

 

[B. Diddy]

Welcome to Android Central! Does the call still go through? Do you have a screen protector or a case on? If so, one of those might be interfering with the proximity sensor, which is located right next to the front-facing camera. If the proximity sensor is triggered (usually by your head, when you hold it up to your ear), it turns off the screen so that you don't inadvertently press a button with your face. But when you take it away from your ear, the screen should come back on. A dirty screen protector or ill-fitting case might make the proximity sensor think it's always up against your ear.