My mic doesn't work in the phone call
My mic doesn't work in the phone call but working in the face time call and voice note
[Re-Titled by Moderator]
iPhone 6
Different mics are responsible for different actions on an iPhone.
To exclude a software bug, restore your iPhone to factory settings and set it up as new. Make sure you back it up before the restoring process.
If the issue remains, schedule an appointment at a Genius Bar or the nearest Apple Authorized Service Provider for diagnostics and possible repair.