I am facing problems on sound from iPhone at time of making call?

Try a Hard Reset:

1. Press volume up (quickly)
2. Press volume down (quickly)
3. Press and hold the power button until the Apple logo ( ) appears

If that didn’t work, it could be a hardware issue. ⚠️

Get expert service and support at the Genius Bar.

▷ Call 1-800-MY-APPLE or get help here. 

See if anything here helps.

iPhone, iPad, or iPod touch - If you hear no sound or distorted sound from your speaker.   *

My iPhone - Why Does My iPhone Make A Static Noise? Here’s The Fix!   -