Can't Hear Call On iPhone 6+

This just started on my plus. I make a call. I can't hear it make the call. No dial tone, no sound of a person answering, nothing. Until it put it on speaker phone. Then things appear normal. The caller is there, I can speak to them and hear them on speakerphone.

I called my neighbor and he can here whether I'm on speakerphone or not. But I can't hear him at all unless it's on speakerphone. I can turn speakerphone on and off and the results always the same. Speakerphone the only way I can hear anyone, but the the person I called can always here me, in either mode.

I rebooted the phone and that did not fix it.

Ideas? Please?