I agree with Finallysatisfied about letting the dealer fix it.
IMHO, if mild soap and water won't make it go away after a couple of washes, the dealer should.
My hood wrap had a flap that had not been trimmed properly and was deflecting the windshield washer fluid flow on the driver's side. I could have trimmed it myself with an exacto knife, but if I slipped and caused a problem with it later, it would be on me, so I had the dealer do it. (AFTER I proved to the service department that it wasn't a dealer installed item...first I had to educate the sales staff...now I have to educate the service staff.
)
Better to keep the liability where it belongs.