Problems with audio on the new UMIDIGI Z PRO

heltonlg

I just bought the new Z Pro.
Yesterday started a problem with the audio. When making calls, I am not heard. I speak, I speak, and nothing from the other person to hear.
The same happens when recording audios in whatsapp, that is, they are not recorded.
But when I use it in the hands-free mode it's okay, it works. When I use a headset, it works.
Only does not work even in private calls mode
I think it's a problem with the microphone, and I need a lot of help solving it.
I work with the phone and I urgently need to sort this out. please help me!
Is it some problem, software or drive that can be solved?
I already did master-reset (factory-reset) and did not solve.
I am in Brazil and there is no UMIDIGI technical assistance here.
If I can not solve this, it was the worst purchase I ever made.
help me!!!
Thank you very much.

my email: heltonlg@gmail.com
google puls profile: Helton Loiola