https://drive.google.com/file/d/1mzK6UwtBcBCuwbP9mhcCpNDAD9J1i266/view?usp=sharing
It's hard to tell from your image rrehanqwer , I think there is a little highlight on the edges. I believe you will notice it more when you get more into the shader. Also the edges of the mailbox has very tight bevels which narrows the angles.
i see.that makes a lot more sense