Android Admob Ads Wont Show Up In App

[AlphaRedDragon]

I have published a free android app and I decided i wanted to add ads so i could make some money for future projects. I looked through the Game maker demo and multiple tutorials.

This is what i have so far in my room create event:

GoogleMobileAds_Init("Admob Id")
GoogleMobileAds_AddBanner("Admob Id",GoogleMobileAds_Full_Banner)
var bw = GoogleMobileAds_BannerGetWidth();
var bh = GoogleMobileAds_BannerGetHeight();
var px = (display_get_width()/2)-(bw/2)
var py = (display_get_height())-(bh)
GoogleMobileAds_MoveBanner(px,py)

This should position the ad at the bottom middle of the screen but its not showing up at all. Is there something im missing here?

any help would be appreciated. Thank you

Sorry if this is the wrong place for this. Let me know if it is and i will move it.