Microphone is not working in this new phone

I just buy one from amazon and arrive working fine except the Mic.. The loudspeaker works but for voice message without using external mic is not workingI’m from Argentina and google doesn’t give me any support. I Know for previous models that is a hardware problem that i need to replace the ic audio but i don’t find anywhere that sold that part or anything like that chip to replace.

Its a new phone without any use, only turn on the phone to find out this