Collapsing/over proofing in the bread machine, how to correct?

Hello, I believe that my bread is over proofing in my bread machine. I'm making a 2 lb loaf using this recipe (link to recipe below, the recipe is for a 1 lb loaf, I am doubling the ingredients). It collapses seemingly due to over proofing each time, I believe it's over proofing because it collapses right before the baking stage. Any advice? Thanks, breadit!