the imported type UnityEngine.Advertisements.Advertisement is defined multiple times

So I have been making an app for the past week and I have finally completed it… well… almost. All I need to do now is add in ads. I have the system for it all put in already and everything, all I have to do is write “Advertisement.Show()”. However, I can’t. Every time I add the script in it gives me the error “the imported type ‘UnityEngine.Advertisements.Advertisement’ is defined multiple times”. I have only been able to find a fourm saying to remove the unity ads assets out of the project because unity ads is built-in now (on unity 5.2, which is what I’m using). However when I do that I get problems where it says I’m missing files and blah blah blah. And when I try and use the package uninstaller, the option to uninstall isn’t there. So either what files should I delete to get ads to work, or how do I get rid of the “the imported type ‘UnityEngine.Advertisements.Advertisement’ is defined multiple times” error. Thank you

From Unity 5.2 and above, Unity Ads has been integrated into the Unity engine and can be enabled using the Services window in Unity. If you previously had used the Unity Ads asset store package and enables Unity Ads from the services window, you must remove the asset store package from your project, otherwise you’ll get the above compile error.

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I have the same issue, I only create a new project and thats it!
I wish you solve this problem.
Thank you,
Myat Fox Games

Just re-import the unity ads library. it is now included with Unity 5.2 and the latest version will work with it being included in the bundle.