One possibility is that one side of the 'insulation' mat that is on the underside of your hood has drooped some. Check the other side and compare them.

As to the 'melted' portion... I'm clueless. The stock plastic cover on my engine rubs in one spot on the 'insulation' pad, but that pad is made from fiberglass mat I think, so I don't see how it could 'melt'.