Ipad pro 12.9” 2021 has no audio voice

the sound work when i play any videos or app background music, until it involve any third party audio voice, like in a zoom meeting, music play via video is good, once it switch to people talking there’s no sound. like background music can be play in pubg mobile i can hear other people talking too until i open my microphone and try to speak, everything sound gone included all the background music and other people talking, but i can hear the pop button when i try to type on ipad keyboard, but a little weird pop sound… I’ve tried all the mute/unmute, volume button, setting > sound > ringer alert, restart, uninstall reinstall app. what else i can do?