You can try: opening the blade, and apply a bit of lateral pressure to the blade on a soft surface like wood or cutting board, this will sometimes 'bind' the lower part of the pivot enough to hold it in place. (Don't break the blade!)
You also might need to loosen the handle screws and recenter the blade, if it's that far off that it's scraping. Loosen all screws recenter the blade, and tighten a little at a time going back and forth between handle screws and pivot until everything is tight again.