Apple - Manufacturing defect Iphone 6S (20 days after purchase)

my self prashanth b n bought iphone *s on ** may ****, within ** days observed a issue where receiver is not working for the same reason i had submitted to authorized service center planet care (banasankari branch bangalore) on ** june ****. i thought it may be software issue but they took the phone and observed it has a manufacturing defect with a faulty component. now they have repaired by physically disassembling the phone.

my concerns are:

*. a phone failed to perform within ** days due to manufacturing defect.
*. after mobile is physically opened i don't trust this device anymore.
*. when i have paid the money for working device why i should accept a faulty/ after repaired device.
*. company claim as superior, high quality & reliable product which is false in my case.
*. continuously denying for replacement for new phone.

many times discussed with apple customer centre and no solution case id: ************.

as a next step, i have already complained in national consumer helpline (complaint number ******). if company didn't reply in ** days i.e **th june ****. will be filing a case in district consumer redressal forums as per consumer protection act **** for the concerns stated and expected resolution as replacement of new phone.