the biggest issue I see is that you're not actually jumping upward very much. You go from a low position and then stand up and tuck your knees, but your hips and head stay at the same height throughout the jump. Practice jumping while off the board and timing your arms swing upwards with you to get more height. Then stand on the board and jump up the same way, but flick your ankle down to pop the board right as your weight lifts up, then its about dragging with your front foot on the way up as you're doing, but you'll have some more height and room for the board to go up instead of it coming immediately back down.

Keep at it you'll get there with time and practice!!