ui.text not seem in android game

i have 3 u.text for bullet and player hp

its showing and work on my pc but doesn’t seem at when I tested on the phone. (i tested htc desire 816 and lg g2 and htc sensation xe)

(i tried arial font and other types)

Is this text property under a Canvas object in the hierarchy?

According to the docs,

The Canvas is the area that all UI
elements should be inside. The Canvas
is a Game Object with a Canvas
component on it, and all UI elements
must be children of such a Canvas.