strange problems in lens preview

We got a very strange issue in lens preview. In the screenshot (link attached), the first 4 seconds is the screen record of my snapping with the lens, while the rest 4 seconds of the screenshot is the preview of my snapping. As you can see, there is no necklace, no hat, no glasses, neither other attached small things, while they should have been expected there.

We have double checked the lens file(1.zip attached), but can not fix the problem. Any one has any idea on this before? Thanks.