[SOLVED] Floating button got hidden in Android

I am using floating action button in page.

But its not working in android device.

When scroll the page sometimes only shows the button.

Device : Lenovo model:: Vibe k5
OS: Android 5.1.1- lollipop

Other devices

Is this placed correctly? It must be a direct child of page

@nolimits4web Thank you for your fine solution.

Now tis working as expected.