Hi @jannava,
Edit : I tested a app that has a audio player ( PWA/not published) and when my screen locks or when I lock my screen the audio still plays. I have a Android phone.
I think when it’s a native app it will play when the screen locks also.
Maybe you can download this app made by Mark and check it. I checked it and when my screen locks the audio still plays.
https://play.google.com/store/apps/details?id=com.angrystew.android
Thank you