Object disappear when lauchning game on Android

Hi.
I have a very strange problem. When I test my Android project on my LG G2, an object (a bench) is no longer visible although I can see it in the viewport.(mobile view) The size is very small (200 vertices). This is not the problem. I exchanged this object with another bench. But the result is the same. This object is not visible when I launch the Android preview.

What is causing this problem? Could this be a bug? I have no explanation for this.

Best regards, Andreas