The other issue that I saw in your vid, besides what ScoutHikerDad already pointed out, is that at times you are putting the shoulder of the razor on the strop. You want just the blade edge on the strop.

You are stropping correctly when you hear just a hiss when the razor moves down the strop. If the sound is loud and the edge feels a little "gravelly" the edge is not there yet from the honing. At least these are a couple of tells that work for me.

Bob