I got a

300S 2018 and i noticed the rear bumper on the driver side is like loose? I guess. And just wondering what part i need. I think it’s missing the clips that’s hold it to the body but I’m not too sure. Here’s the picture.

 

Try this. From the bottom, lift it gently out and sharply up to get the bumper to connect and latch.

 

Yea it will go on there but after driving it, it just comes back off it doesn’t stay attached,

 

Maybe you can take it to a body shop to fix ?