How to resolve Duplicate files copied in APK META-INF/rxjava.properties

I am using rxjava and rxvolley on my android aplication. When I try to run it I get this error

Execution failed for task ':testapp:transformResourcesWithMergeJavaResForDebug'.
> com.android.build.api.transform.TransformException: com.android.builder.packaging.DuplicateFileException: Duplicate files copied in APK META-INF/rxjava.properties
            File1: C:\Users\Daniel\.gradle\caches\modules-2\files-2.1\io.reactivex\rxjava\1.1.0\748f0546d5c3c27f1aef07270ffea0c45f0c42a4\rxjava-1.1.0.jar
            File2: C:\Users\Daniel\.gradle\caches\modules-2\files-2.1\io.reactivex.rxjava2\rxjava\2.0.3\d2f725668bd22e21170381b23f8fbdf72c69d886\rxjava-2.0.3.jar

I have a exclude.gradle file like this

android {
packagingOptions {
    exclude 'META-INF/DEPENDENCIES.txt'
    exclude 'META-INF/NOTICE'
    exclude 'META-INF/NOTICE.txt'
    exclude 'META-INF/LICENSE'
    exclude 'META-INF/LICENSE.txt'
    exclude 'META-INF/rxjava.properties'
    exclude 'META-INF/rxjava.PROPERTIES'
    exclude 'META-INF/RXJAVA.properties'
    exclude 'META-INF/RXJAVA.PROPERTIES'
    exclude 'META-INF/rxjava'
    exclude 'META-INF/RXJAVA'
}

lintOptions {
    abortOnError false
}
}

How can I fix this problem?

I had the same problem. The way I fixed it is adding the packagingOptions in app gradle as described in Duplicated file rxjava.properties

android {

    defaultConfig {
    }
    buildTypes {
    }
    packagingOptions{
        exclude 'META-INF/rxjava.properties'
    }
}