Looking to fix this strip in a cape cod house at the peak. The angle is maybe around 20 degrees? It's fairly shallow. The strip is some type of tough material, definitely thicker than regular drywall tape, and 2 1/2" wide. I pulled it down slightly in March, pushed joint compound in the whole length, and pressed it tight, then smoothed additional joint compound over the top. It looked ok and held until late May when it got hot out.
How do I fix this so it doesn't come off again?