How to fix error 'classcastexception' with using Freetts

Question

I just want to use Freetts testing with this code but i got an error:

ClassCastException: class com.sun.speech.freetts.en.us.cmu_us_kal.KevinVoiceDirectory cannot be cast to class com.sun.speech.freetts.VoiceDirectory (com.sun.speech.freetts.en.us.cmu_us_kal.KevinVoiceDirectory is in unnamed module of loader com.sun.speech.freetts.DynamicClassLoader @23bc24e9; com.sun.speech.freetts.VoiceDirectory is in unnamed module of loader 'app')

What's the problem?

I already put libraries.

import com.sun.speech.freetts.VoiceManager;

public class  Voice {
    private String name;
    private com.sun.speech.freetts.Voice voice;

    public Voice(String name) {
        this.name = name;
        this.voice = VoiceManager.getInstance().getVoice(this.name);
        this.voice.allocate();
    }

    public void say(String something) {
        this.voice.speak(something);
    }

    public static void main(String[] args) {
       Voice voice = new Voice("kevin16");
       String say ="hi";
       voice.say(say);
    }
}