Why does the 3D plot deform after a data tip appears?

Hello,

I have a 3D sphere surf plot, all axes lim is set to [0 1]. When I want to get value from sphere surface by using data cursor the data tip appears but after rotation through Rotate 3D tool the sphere plot is deformed. Sphere is not sphere anymore. Can you tell me why this is happen and how can I fix it?

Thank you in advance,

Tom