Apple India — Brand new iphone se not functioning properly

Address: Kolkata, West Bengal, 700068

The microphone of the Mobile Device is not working. Even after having getting the device diagnosed at the authorized Service Centers multiple times, the problem is still persisting. I have even contacted the Apple India's Customer Care several times. That did not help either. This is really harassing. This kind of a performance is not expected from a brand like Apple. I require a fix immediately.