Who has the same problem with me?
In order to better explain this problem, I recorded the video. ,Please check. Thank you!
It looks like the inner race of the bearing doesnt have a matching chamfered profile for the press ring to sit against.
How did you select which headset? Which frame model exactly do you have?
All the parts look fine, and act how I'd expect that style of headset should. However it shouldn't look like that assembled. The gap might not be perfect, as that design does allow for some misalignment, but it shouldn't be so visibly squint.
I'm going to assume you've done the basics like check the bearings are sitting on their relative chamfers in the headtube (they should be free to wiggle a bit once seated), as a bearing that's not seated can cause that. Also have you checked the lower bearing, and it's seat on the fork is correct?
If everything looks OK, then I'd be checking the frame. On a mountainbike, I'd be looking to make sure nobody had put an offset cup in the wrong way, as that would give that same end result.
You sure that split ring isn't the crown race and that you don't have components from the top and bottom mixed up?