Buttons don't work with AdMob

I have followed the tutorial provided by Google and installed the unity package. I am building for android devices only.

https://developers.google.com/mobile-ads-sdk/docs/games#unity

https://github.com/googleads/googleads-mobile-plugins/releases/tag/v2.2

I used the source code at the github link and I modified the GoogleMobileAdsDemoScript.cs script so it loads the banner ad when the game starts. When I run it on my phone the banner ad shows but the buttons don't work. The buttons will show but when I press them they don't change colour. The buttons will work in the editor though just not on my phone.

I have tried using canvas buttons and they don't work either. The buttons still don't work when i turn off the GoogleMobileAdsDemoScript.cs script. It's as if installing the package disables all buttons. I am using Unity 5 as well.