as said above , sounds like worn hinges...or adjustment...most likely worn though..

adjust them by loosen the bolts to the fender "slightly"...then open the hood all the way, have someone hold it open all the way , tighten down the bolts...usually its the rear bolts that need the adjusting....maybe start with those first.

to see if they are worn...
have someone open the hood and close it (not all thay closed) ,while you look closely at the hinges, where the pivot occurs ,see if they move or slide...
I had over a 1/4" slide in mine before I replaced it...