My sound cuts off on the other end of video calls

Hi, i have a problem that's making me wonder if I should get my iPhone 12 fixed.

The problem presents itself when i'm in a video call, either on FaceTime or whatsapp. On the other end they hear my audio cracking up whenever they make sound. For example, when I'm FaceTiming my mother and my sister is talking in the background or my mother is making noise with her chair or coughing, the sound of the video call (and so my voice) completely goes quiet on her end. So they have to sit completely still and make no noise in order for them to hear me.

I do hear them when I make noise on my end (for example doing the dishes while talking to them), but when they do that my they can't hear anything I'm saying. And no, they don't have bad hearing, haha. Their phone literally stops making sound.

I've tested if its just my device, and it is. I have this when I call my friends too.

I would like to know if there s a way to fix it, and if its going to cost me a lot of money, haha. Its been doing it since I received the iPhone so I guess its a factory issue?

Thank you!