Iphone 12 pro max Dark Spots inside steel frame

Hello,

On Saturday I got new Iphone 12 pro max 256 GB pacific blue and while checking it out I found these strange BLACK MARKS on the right side(on the power button side) of the steel frame as shown in the picture. I have tried to wipe the frame with normal cotton piece but still no luck. Seems like it's inside of it.. Now sharing with you guys and wondering is this the quality that I paid for ???