Delamation

I have a small area under my clearence light on the front of my trailer that has delamation. I am sure a bit of water got in there. I would like to reglue it. I will take a 2x4 and use a cargo strap and press it tight. My question what kind of glue would be the best. Its only about a 6 inch square and there is no wayer damage inside. Any suggestions?