Unispin problem.

Hello, just learned 180 unispins yesterday and this morning I landed 4 in a row…
but a new problem has arisen that I didn’t have yesterday–I keep hitting the middle of my left leg (inside between the shin and calf) against the flat part of the crown on my Nimbus X frame, kinda painful after the first 10 or so…

Am tilting the uni to the side, not getting it around fast enough, catching it funny or what?