on android,i'm not get shadow with Sphere

i’m chinese,my english is not good,i hope get help,thank you。

the environment:
1.OS is MAC。
2.LUMEN has opened。

the Sphere shadow is different between MAC and Android。

MAC:the Sphere has shadow。
Android:the Sphere don’t has shadow,but Sphere move up,the shadow can here,but move to backgroud,the shadow don’t has shadow。

oh,i find that shadow can visible when the sphere‘'s size > 1 or distance is very short。

is a bug,the pc and android is very different。the Cascades Shadow is a big bug on android。