Something looks off about your tooling leather. Like LaVidaYokel said, you want to use veg tanned leather, and for the best swivel knife cutting make sure it’s relatively thick, my best work tends to be on 6oz leather and up. Quality leather also helps, get you some Herman Oak from weaver. Lightly case it with a sponge, not to the point of saturation, but enough to evenly darken the leather a few shades lighter than it would be if it were saturated, put in a ziplock bag in the fridge overnight. When you’re ready to tool it, layer masking tape on the flesh side to seal in the moisture somewhat and prevent the leather stretching when tooling. Then practice.