Transform.position.x jumps to high numbers after collision

In the game rectangles move foward on the x-axis as players. As soon as they collide with one of the obstacles their x-position jumps to very high values (for example collision was at x=40, jumps to x=240);
The obstacles have a box collider and the rectangles have a polygon collider. Any idea what might cause that?
Thank you

Try setting rigidbody to kinematick