Steering column play?

[Exp21]

Good morning everyone. My w245 has an issue. I hear some stonks and clonks and stocs at low speed maneuvering, while parking, in particular when there's charge transfer during braking. I replaced many things: control arms, brakes, sway bar links, outer tie rods, cv joint. Car has been seen in two workshops, but no mechanical play has been found in any component. I was thinking about the noise and I came to a conclusion. I parked the car, lifted the hood and noticed that gently grabbing and shaking the steering shaft it has a play (I hear clonk while shaking it). Is there someone who knows exactly what could be the problem? Do I have to change the steering joint or the entire column/shaft? Thanks for help!