Whenever I try to do extend my legs in adv tuck FL I fall down I can do One leg FL can anyone help plz

I made a simple planche simulator. It has multiple body parts and lengths, it calculates the center of mass and adjusts the tilt of the arms. Also, it shows the force that the shoulders have to do this doesn't take into account the scapula, but you can simulate it by just adding it to the arm length for example, I measured my arm length at 58cm then I measured again with scapula protraction, and it measured 70cm, this shows the power that the scapula has. This also shows why doing a planche at a higher or lower angle is easier, and also with bent hips. Take the numbers with a grain of salt is a very simple model. https://editor.p5js.org/muxiku/full/Xtu3SVAk8