I was wondering why no one asked what foot forward and which side of the ski your rope was on. If you’re left foot forward like me, the rope needs to be on the right edge of the ski and if you are right foot forward put the rope on the left side. I can’t get up if I reverse these or at least it’s almost impossible.
If the rope is correct and that’s not the problem then you probably are not getting the ski moving forward and rising before you push with your legs. Push with your legs and the ski is to perpendicular to the surface.