As the error message suggests you are not excluding the META-INF/LICENSE
file which exists in more than one of your dependencies
com.android.build.api.transform.TransformException: com.android.builder.packaging.DuplicateFileException: Duplicate files copied in APK META-INF/LICENSE
packagingOptions {
exclude 'META-INF/NOTICE' // will not include NOTICE file
exclude 'META-INF/LICENSE' // will not include LICENSE file
// as noted by @Vishnuvathsan you may also need to include
// variations on the file name. It depends on your dependencies.
// Some other common variations on notice and license file names
exclude 'META-INF/notice'
exclude 'META-INF/notice.txt'
exclude 'META-INF/license'
exclude 'META-INF/license.txt'
}