3D UI actors position not updated each frame (only visualy ?)

it's been 2 RV projects that I've had this problem. I can't move my 3D UI elements in real time. Here is an example:

I made a behavior to make a webview always stay close (and in front) of the user. When I use this behavior on a basic actor like a cube, the actor works like expected. But when I use it on a 3D actor like a 3D Webview, it doesn't move, it stays at its starting position and its position is randomly updated when I perform certain actions (when I use the trigger of my VR controller for example, or when a new Webview is activated). This seems to be a visual bug because even during editing, when I try to move my 3D Actor, it happens that the visual doesn't move anymore, only the outline. In this case, I have to restart creative to be able to see the new position of my actors.

How can I fix this problem?

@NK @DN