Prints are distorted or squeezed

[ReneH]

Hello,

i get my Mars 2 pro. I printed the Rook and anything goes well. Now i try to print my own model and it comes out distorted or squeezed, see the pictures.

My X-resulotion: 1620 and Y-resulotion: 2560, Lock ratio is activated. Has anyone an idea where the error is?

Thank you