One of canvas disappears after build on Android

I have 3 canvas, and have two different layers for them. Two canvas using default UI layer and one using custom layer called "BackUI".

And I have two cameras that render each UI and BackUI layer only. The problem is, when I build my game and try with my smartphone, BackUI canvas not rendering at all.

So I turned off one of UI layer canvas and now I can see BackUI canvas. There is no script attached on each canvas objects.

What makes BackUI canvas disappears? Is there a some kind of number of limits in canvas or UI objects for android device? Because it was worked before, but suddenly BackUI canvas not rendering and turning off one of UI canvas make it work.

This reminds me some kind of old console system, there is a number of limits of sprites can render. Anyway if do, how do I check the limit?

Or is there something that I missed? Couldn't find any related problem like this. Any advice will very appreciate it. Using Unity 2018.3.12f1.