DEBUG mode is not called if project is in Objective-C

If the project is in Swift DEBUG mode is called and return google ads test ID. But if the project is in Objective-C DEBUG mode is not called and return real ads ID. Any help is appreciated.

#if DEBUG
    return "ca-app-pub-3940256099942544/3419835294"
#else
    return "ca-app-pub-*****/*****"