I can't understand how the design study receives such an angle? Instead of 30 degrees it shows 1900 degrees! How?!

Model: two plates are connected at one point hinged on diagonally opposite points of the coupling spring. Normal calculation in the Motion Study shows maximum displacements of about 33 degrees. When trying to solve optimization problem with a single variable in the spring rate, the result of solving an optimization problem to get the values of the angle of inclination of about 2000 degrees.

I'm at a loss.