JSF - Getting NullPointerException in constructor when accessing getFacade()

JSF - Getting NullPointerException in constructor when accessing getFacade()

this code produces NullPointerException. I don't know why. When I put the
code from constructor to some other void with @PostConstruct - it works. I
tried to initiate klientFacade - but it's not working, either.
package view;
import entity.Klient;
import facade.KlientFacade;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import javax.annotation.PostConstruct;
import javax.ejb.EJB;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.ViewScoped;
import static util.Messages.addFlashMessage;
@ManagedBean
@ViewScoped
public class ManageClient implements Serializable {
@EJB
private KlientFacade klientFacade;
private List<Klient> clientList;
public List<Klient> returnClientList(){
return getKlientFacade().findAll();
}
public ManageClient() {
clientList = new ArrayList<>();
clientList = returnClientList();
}
public String removeClient(Klient klient){
addFlashMessage("Klient ["+klient.getLogin()+"] zosta³ usuniêty.");
getKlientFacade().remove(klient);
return "manage";
}
public List<Klient> getClientList() {
return clientList;
}
public void setClientList(List<Klient> clientList) {
this.clientList = clientList;
}
public KlientFacade getKlientFacade() {
return klientFacade;
}
public void setKlientFacade(KlientFacade klientFacade) {
this.klientFacade = klientFacade;
}
}