The manager is always null :( (Please help me , i have a family)

[sussolinoss]

Main Class:

public final class JuicePvPAC extends JavaPlugin {

public static JuicePvPAC plugin;

public static String prefix = Verbose.color("&6『&eVanessa&6』&7>> &f");

public void onEnable() {
    plugin = this;
    if (Bukkit.getPluginManager().getPlugin("ProtocolLib") != null) {
        ProtocolLibHook.register();
    }
}

}

ProtocolLib Hook:

public final class ProtocolLibHook {
public static void register() {
ProtocolManager manager = ProtocolLibrary.getProtocolManager();
if (manager != null) {
manager.addPacketListener(new PacketAdapter(JuicePvPAC.plugin, PacketType.Play.Client.USE_ENTITY) {
@OverRide
public void onPacketReceiving(PacketEvent e) {
if (e.getPacketType() == PacketType.Play.Client.USE_ENTITY) {
PacketContainer packet = e.getPacket();
UUID id = packet.getUUIDs().read(0);
Entity t = Bukkit.getEntity(id);
Player p = e.getPlayer();

                                              double x = packet.getDoubles().read(0);
                                              double y = packet.getDoubles().read(1);
                                              double z = packet.getDoubles().read(2);

                                              Location pLoc = new Location(p.getWorld(), x, y, z);
                                              if (t != null) {
                                                  Location tLoc = t.getLocation();
                                                  controlCheck(p, pLoc, tLoc);
                                              }
                                          }
                                      }

                                      private void controlCheck(Player suspect, Location p, Location t) {
                                          double distance = p.distance(t);

                                          Verbose.debug("Distance: " + distance);

                                          if (distance <= 3) {
                                              Verbose.debug("Flag [OK] distance = " + distance);
                                          } else if (distance >= 3.3 && distance <= 3.50) {
                                              Verbose.verbose(suspect, "Reach [C]");
                                          } else if (distance >= 3.50 && distance < 4) {
                                              Verbose.verbose(suspect, "Reach [B]");
                                          } else if (distance >= 4) {
                                              Verbose.verbose(suspect, "Reach [A]");
                                          }
                                      }
                                  }
        );
    } else {
        getLogger().warning("(!) ProtocolLib non si è caricato (!)");
    }
}

}