How can I fix the mic

Hi,

Connect the earphones with the microphone attachment and either make or receive a call.

If your voice can be heard then the voice transmission circuitry of the phone is OK but there is a problem with the microphone.

If your voice cannot be heard then there is most probably a problem with the systemboard in the phone.

Here is a link to a video which shows how to disassemble your phone.

https://www.youtube.com/watch?v=IWwZLrHq...

Unfortunately it doesn't show the microphone, but if you have proven that the problem is with the microphone and wish to investigate to see if you can spot the problem, here is a link that shows what the microphone looks like. It should be positioned near the voice input hole on the bottom of the phone.

https://www.aliexpress.com/item/2PCS-Ori...

If opening and checking your phone seems to daunting then I suggest that you take it to a reputable, professional phone repair service and ask for a quote for a repair.