Hello Gayle! I struggle with it as well, but have noticed that it helps to practice e.g. with a Foam Roller, lifting the pelvis up and therefore starting the movement in an easier position. Or, you could work some more on the lower-abs "tugging" motion that brings the legs back by just lifting them up and practicing lifting your pelvis off the ground, but without necessarily having to go back yet.

I'm still struggling with it as well (I have quite long legs and a heavy pelvis, so sometimes it's just physics ;) ) but hope this helps!