Shaky license plate holder

[SFL_driver]

Anyone have any ideas why my rear license plate frame holder won’t tighten all the way down? Screws are both full tight. It feels like the bolts have bottomed out but the head still has some space between it and the bottom of the plate holder. Bolts are T-25, 25mm long.
United States
Video:

View: https://youtu.be/Or0AFX1aY2Y?si=QL5mHBE5tn6uGLg6

 

[Jiman01]

Appears that the bolt head is too small for the opening in the plate? Seems like there should be some tube spacers or washers

 

[SFL_driver]

Appears that the bolt head is too small for the opening in the plate? Seems like there should be some tube spacers or washers

The bolt head diameter seems okay. It feels like the bolt is bottoming out (too long) before the head can meet the plate holder to apply pressure.
Seems like either the bolts are too long or the plate holder is somehow not correct.
Throwing a couple washers on each bolt would surely solve the issue but I shouldn’t have to Jerry rig something on a brand new vehicle.
Maybe the bolts or holder are the parts for the front license plate (which we don’t use in my state).

Can anyone confirm if 25mm is the correct bolt length on their vehicle?