People can’t hear my voice on calls

Re: People can’t hear my voice on calls

Check you are not on "mute" during a call: While on a call on iPhone - Apple Support

says:

"When you’re on a phone call:

Adjust the audio during a call

To change the volume, press the volume buttons on the side of iPhone

(make sure "mute" is not on)

Else:

What to do: If the microphones on your iPhone aren't working - Apple Support