Revolute joint control degrees

Good day, I am currently busy with a project that involves controlling a rotery inverse pendulum. I am currently running into a problem where the revolute joint is not really following the input position I require of it. The input Theta and Phi (See figure one) is given in the second figure that displayes the inputs and outputs of the angles on a scope (they match). My CAD model or digital twin can be seen in the third figure. The problem is, however, that my pendulum goes gelicopter mode and does not follow the alpha input at all. This is my first time using simulink with a CAD model and help would be greatly appreciated! Thanks in advance.