Universal Mobile Ads for iOS & Android

I keep getting this whenever I try to build I am not sure what is happening - can anyone help?

UATHelper: Packaging (Android (All)): UnrealBuildTool: ERROR: C:/NVPACK/android-sdk-windows/tools/android.bat failed with args --silent update lib-project --path JavaLibs/adcolony-3.1.2.0 --target android-23
UATHelper: Packaging (Android (All)): UnrealBuildTool: Total build time: 26.69 seconds (Local executor: 17.39 seconds)
UATHelper: Packaging (Android (All)): CommandUtils.Run: Run: Took 26.9096753s to run UnrealBuildTool.exe, ExitCode=5