This is the first time DE Composer doesn't work with my level, I have no idea how to debug in this case.

In Aximmetry DE Composer, I dropped my project into a conpund and linked its Out to the Rendered of a VirtualCam_Unreal_A-B_Preview_3-Cam, which out to a channel out, also connected their camera data.

Not only the virtual camera is stuck, all the input pins I set up doesn't work as well. I could see the Niagara system and a Stage TV, which didn't respond to the video input and a logical pin.

The level has a player start (out of sight), an Aximmetry_Virtual_Camera_1-3_Billboards, a Niagara and a very basic stage lighting and TV with a box reflection and a planar reflection.

In project setting, I set the maps to be the level I wanted, change Custom Depth-Stencil Pass to Enabled with Stencil, and enable global clip plane.

In level bluepring, I set up changable stage light color, adjustable Niagara Spawn rate, and a TV video input. None of those pins respond in DE Composer.

The only problem I ran into was it was saying the Player Start is in bad size, so instead of place it underground, I move it to the side, out of walls.

All the past levels run smoothly, just this one is compeletely unuseable.

(Although the video is in, the TV is still the default texture, while the camera is stuck at this view)

What could be the problem?