Why model disappears after building apk in Unity3D?

Question

Unity

After building the project in apk, the model with the video that is needed for the background disappears.
Unity started to work recently, you can say the teapot
Tell me what the problem is please
This is after the build:

And this is in the editor:

Answer 1

In general, I solved the issue this way, I deleted that cube with the screwed video and just pulled the video file itself onto the stage