On my android, when I get a call I can hear them but they cannot hear me? What can I do?

[AC Question]

android 4.1.1

 

[B. Diddy]

Welcome to Android Central! Which phone? Can they hear you if you turn on speakerphone, or use a wired/Bluetooth headset? If so, then the primary phone mic is either broken or blocked by something. Make sure there isn't any debris clogging the mic opening.