2 ways to fix it.

Very thin double sided tape on top edge (I think smallest 3m makes is 5mm wide), or a bead of windshield urethane adhesive, then reinstall plate, screw in top 3 mounts, and press/tape the top edge in place for 24 hours while it cures.

Either way should solve it. You won't need to remove the plate anyway as you can remove the bumper with it installed.

Try it out and let me know, I won't have mine back till next week, you can get the 3m tape or windshield urethane (black) from AutoZone, Advance, pep boys, etc....

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2018 Ram 2500 6.7L Cummins 68RFE
19k miles -Bright White/Black - Big Horn Sport - Crew Cab Short Bed
2013 X5 35D (CEO's) - Born on 5/17/2013 -
82k miles - Alpine White/Cinnamon Brown/Premium Pkg, Sport Activity/Premium Pkg and Sound/20" Style 214/Running Boards