Unity Ads only loading on my device not other peoples,

Hi,
I have made a game and released it on the Google Play store -
http://play.google.com/store/apps/details?id=com.prov007.UFOno

The game works fine and the Ads are showing after 5 deaths like i scripted on my phone and unity editor but i have checked with other people that have downloaded it and Ads aren’t showing for them on their device.

Can anyone please share some insight as to why this is happening.,Hi,

Somebody please help me, this is my first ever game and i work alone and don’t want to miss out on any revenue