narrowing and widening at certain height

[Zolo]

My Kobra 2 Neo makes a narrowing and widening at same level with ech print. It makes layers thinner and thicker. this occurs in both directions: x, y, in and out, so I presume that it has something to do with z axis. the element (I don't know what to call it) placed on the threaded rod, which controls the z axis, seems terribly poorly made. it looks as if it was open and could not be closed because the elements do not fit together. it is loose, dangles and creaks. I am attaching a video.
What can be done to fix that?
the printer is pretty new, so it is not about elements being worn out. Maybe I should just contact anycubic support?


IMG-20241106-233233186.jpg

[Zolo]

Nothing? Nobody willing to help?

[Bikeracer2020]

From the video it looks like the lead screw nut is missing.

[Zolo]

Thank you.
I added a video what shows how it looks like. and yeah, it seems like there's something missing - it's loose. I can really compare it to what it should look like, but I don't even know how to call this thing. Could tell me how should I google it?

[Bikeracer2020]

Perhaps contact manufacturer and or retailer and explain the problem.