CommandInvokationFailure: Gradle build failed when using Unity Ads

I can not build my game anymore since this message apeared when I try to build :


CommandInvokationFailure: Gradle build failed.
C:/Program Files/Java/jdk1.8.0_191\bin\java.exe -classpath "C:\Program Files\Unity\Editor\Data\PlaybackEngines\AndroidPlayer\Tools\gradle\lib\gradle-launcher-4.2.1.jar" org.gradle.launcher.GradleMain "-Dorg.gradle.jvmargs=-Xmx2048m" "assembleRelease"

stderr[

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':transformDexWithDexForRelease'.
> com.android.build.api.transform.TransformException: com.android.ide.common.process.ProcessException: java.util.concurrent.ExecutionException: com.android.dex.DexException: Multiple dex files define Lcom/unity3d/ads/BuildConfig;


please help fast !

 

You probably have the "Unity ads" library included more than once (possibly - once in the project and another one by checking it under the "Services" tab).

 

And how can I do that ?

 

Look for the unityads jar or aar file in your project, and remove it (if indeed you are including unity ads from the "services" tab).

 

Thank's you so much it's working !