Thick-Walled Cylinder - Equivalent Von Mises

Hi

I am calculating equivalent von mises stress with following equation for cylinder loaded with internal pressure and axial load.

All three principle stress and max shear stress are from thick walled cylinder formula from Roark table 13.5. I built FEA for this my hand calculated von mises stress from equation above does not match with FEA although my FEA is validated, Any thoughts.

thanks