The leaks occur at the corners with the glob of adhesive/sealant. These corners looked exactly like this on both of our Sheer Descents.That "sealant" looks to be epoxy. You can't put a "band-aid" on a pressure leak and expect it to hold, they always fail. Before replacing that sheer, try to get the epoxy off and use PlastAid. Clean the area well, perhaps very light sanding, and dry it. Mix the product to "pancake batter" consistency and pour it onto the area. The solvent in the PlastAid will etch into the plastic body of the sheer and chemically weld to it, very different from just sticking on the surface. Once dry (about 15 minutes depending on the temperature) it is a permanent repair.