Any residual adhesive or debris on the frame will prevent your screen from sealing properly.

Use the flat end of your spudger to scrape off as much adhesive from the frame as you can.

Use tweezers or your fingers to peel and remove any remaining adhesive.

Clean the perimeter of the frame with a small amount of highly-concentrated isopropyl alcohol (over 90%) and a lint-free or microfiber cloth.