Sound quality problem when I used head phone

I use iPhone XR. When I listen to the music with my headphones which I got from iPhone, the sound quality is not good. It like every instrument located in the middle stage or it like monotone. However, when I try with my friend's phone who also use iPhone XR with the same app, music, and headphones, I found that the sound is very different. The sound of my phone's friend is very good and shows the stereo sound. I am not audiophile. I am a music lover. The different of sound quality between me and my friend's phone is very clear. I pretty sure that this problem is not from my headphones.

Moreover, I try with Bluetooth headphones the sound quality is the same as my headphones. This mean that the sound driver on my phone might be a problem.

Do you face this problem like me and How to fix it?