Air leaking into freezer through door dispenser

I followed the video instructions. They were clear and consise. I removed the trim ring and controls. Them removed the housing and flapper. I did notice a small burr in the plastic chute and foam insulation. I trimmed this off with a utility in hopes this burr caused the flapper to warp. This is the 2nd time the flapper has been replaced in 1.5 yrs. The repair was really easy thanks to the video.