Dough not rising

I’m making this recipe https://food52.com/recipes/87219-sourdough-kanelstang-recipe, and there doesn’t seem to be any rise after the overnight proof. My starter was active and almost tripled before using. I put it in a proofer at 77 F, so temperature should have been fine. Is there a way to rescue this, maybe work instant yeast into the dough? Should I just try shaping it and see what happens? Any help would be appreciated. Thanks!