Got it–I’ve been there as well. Be patient with yourself. What helped me the most was focusing intently on using Passively released air. I actually took sort of an extreme approach and didn’t play the exercises as suggested, alternating between Active and Passive air. I suggest following the WindWorks course closely, more than I did, but focusing on playing with Passively released Air really helped me, I believe, focus in on how Shape impacts the production of sound and the resonance/efficiency of the sound produced.

I also spent a lot of time checking to make sure I was having a sympathetic vibration in the lower register at softer volumes.

I recommend not focusing too much on the dynamics at first, at least not while experimenting with the balance of Shape and Air. I would play as softly as you can comfortably while releasing air passively. In time, your ability to play softer and softer more comfortably will increase. That was my experience, anyway.

Good luck!