I drew in PDEtool box GUI a beam clamped on each ends. Is it normal that Eigenvalue depend on mesh refinement ?

Hello,

I would like to find the resonance frequency of a 2D clamped beam using the PDE toolbox, Structural Mech. I compute the same problem on Comsol but I don't find the same eigenvalues, why ? Why does the eigenvalues change when I refine the mesh even if I start with a lot of nodes in my initial mesh ?

Thank you for your help, regards

Jacques