Moving Mesh for moving object

Hello,

i have two objects. One of them is static and has a high constant temperature. The other one, which should have contact with the hotter object, has a velocity in z direction. So i choose the physics "heat transfer in solids" and "moving mesh(ale)". Boundaries at "heat transfer should be clear". In "moving mesh" i take "free deformation" and select the object to move and the the prescribed mesh velocity and select all surfaces of the object.
My problem is that the contact between two objects is interrupted after the moving of my object ( i can see it on my temperature distribution). What could be the reason for that?

Thanks
Tolga