Program: 81415
Project: 81415
Buggy source:
public void onPlayerMove(PlayerMoveEvent event){
  if (event.isCancelled())   return;
  if (Jail.prisoners.containsKey(event.getPlayer().getName().toLowerCase())) {
    JailPrisoner prisoner=Jail.prisoners.get(event.getPlayer().getName().toLowerCase());
    if (prisoner.isBeingReleased())     return;
    prisoner.setAFKTime(0);
    JailZone jail=prisoner.getJail();
    if (!jail.getSettings().getBoolean(Setting.EnablePlayerMoveProtection))     return;
    if (!jail.isInside(event.getTo())) {
      if (jail.getSettings().getString(Setting.PlayerMoveProtectionAction).equals("String_Node_Str") && prisoner.canGuardsBeSpawned() && (!Util.isServer18() || event.getPlayer().getGameMode() == GameMode.SURVIVAL)) {
        if (prisoner.getGuards().size() > 0) {
          for (          Wolf w : prisoner.getGuards().toArray(new Wolf[0])) {
            if (w == null || w.isDead()) {
              prisoner.getGuards().remove(w);
              Jail.guards.remove(w);
              continue;
            }
            if (w.getTarget() == null)             w.setTarget(event.getPlayer());
            if (jail.getSettings().getInt(Setting.GuardTeleportDistance) > 0 && (w.getWorld() != w.getTarget().getWorld() || w.getLocation().distanceSquared(w.getTarget().getLocation()) > jail.getSettings().getInt(Setting.GuardTeleportDistance)))             w.teleport(w.getTarget().getLocation());
          }
        }
 else         prisoner.spawnGuards(jail.getSettings().getInt(Setting.NumbefOfGuards),event.getTo(),event.getPlayer());
      }
 else       if (jail.getSettings().getString(Setting.PlayerMoveProtectionAction).equals("String_Node_Str")) {
        prisoner.delete();
        plugin.getServer().broadcastMessage(event.getPlayer().getName() + "String_Node_Str");
        return;
      }
 else {
        if (!prisoner.canGuardsBeSpawned()) {
          Jail.log.warning("String_Node_Str" + prisoner.getName() + "String_Node_Str");
          prisoner.setGuardCanBeSpawned(true);
        }
        if (jail.getSettings().getInt(Setting.PlayerMoveProtectionPenalty) > 0 && prisoner.getRemainingTime() > 0) {
          Util.Message(jail.getSettings().getString(Setting.MessageEscapePenalty),event.getPlayer());
          prisoner.setRemainingTime(prisoner.getRemainingTime() + jail.getSettings().getInt(Setting.PlayerMoveProtectionPenalty) * 6);
          InputOutput.UpdatePrisoner(prisoner);
        }
 else {
          Util.Message(jail.getSettings().getString(Setting.MessageEscapeNoPenalty),event.getPlayer());
        }
        Location teleport;
        teleport=prisoner.getTeleportLocation();
        event.setTo(teleport);
      }
    }
 else     if (jail.getSettings().getString(Setting.PlayerMoveProtectionAction).equals("String_Node_Str")) {
      for (      Object o : prisoner.getGuards().toArray()) {
        Wolf w=(Wolf)o;
        prisoner.getGuards().remove(w);
        Jail.guards.remove(w);
        w.remove();
      }
    }
  }
}

Fixed version (ground truth):
public void onPlayerMove(PlayerMoveEvent event){
  if (event.isCancelled())   return;
  if (Jail.prisoners.containsKey(event.getPlayer().getName().toLowerCase())) {
    JailPrisoner prisoner=Jail.prisoners.get(event.getPlayer().getName().toLowerCase());
    if (prisoner.isBeingReleased() || prisoner.getJail() == null)     return;
    prisoner.setAFKTime(0);
    JailZone jail=prisoner.getJail();
    if (!jail.getSettings().getBoolean(Setting.EnablePlayerMoveProtection))     return;
    if (!jail.isInside(event.getTo())) {
      if (jail.getSettings().getString(Setting.PlayerMoveProtectionAction).equals("String_Node_Str") && prisoner.canGuardsBeSpawned() && (!Util.isServer18() || event.getPlayer().getGameMode() == GameMode.SURVIVAL)) {
        if (prisoner.getGuards().size() > 0) {
          for (          Wolf w : prisoner.getGuards().toArray(new Wolf[0])) {
            if (w == null || w.isDead()) {
              prisoner.getGuards().remove(w);
              Jail.guards.remove(w);
              continue;
            }
            if (w.getTarget() == null)             w.setTarget(event.getPlayer());
            if (jail.getSettings().getInt(Setting.GuardTeleportDistance) > 0 && (w.getWorld() != w.getTarget().getWorld() || w.getLocation().distanceSquared(w.getTarget().getLocation()) > jail.getSettings().getInt(Setting.GuardTeleportDistance)))             w.teleport(w.getTarget().getLocation());
          }
        }
 else         prisoner.spawnGuards(jail.getSettings().getInt(Setting.NumbefOfGuards),event.getTo(),event.getPlayer());
      }
 else       if (jail.getSettings().getString(Setting.PlayerMoveProtectionAction).equals("String_Node_Str")) {
        prisoner.delete();
        plugin.getServer().broadcastMessage(event.getPlayer().getName() + "String_Node_Str");
        return;
      }
 else {
        if (!prisoner.canGuardsBeSpawned()) {
          Jail.log.warning("String_Node_Str" + prisoner.getName() + "String_Node_Str");
          prisoner.setGuardCanBeSpawned(true);
        }
        if (jail.getSettings().getInt(Setting.PlayerMoveProtectionPenalty) > 0 && prisoner.getRemainingTime() > 0) {
          Util.Message(jail.getSettings().getString(Setting.MessageEscapePenalty),event.getPlayer());
          prisoner.setRemainingTime(prisoner.getRemainingTime() + jail.getSettings().getInt(Setting.PlayerMoveProtectionPenalty) * 6);
          InputOutput.UpdatePrisoner(prisoner);
        }
 else {
          Util.Message(jail.getSettings().getString(Setting.MessageEscapeNoPenalty),event.getPlayer());
        }
        Location teleport;
        teleport=prisoner.getTeleportLocation();
        event.setTo(teleport);
      }
    }
 else     if (jail.getSettings().getString(Setting.PlayerMoveProtectionAction).equals("String_Node_Str")) {
      for (      Object o : prisoner.getGuards().toArray()) {
        Wolf w=(Wolf)o;
        prisoner.getGuards().remove(w);
        Jail.guards.remove(w);
        w.remove();
      }
    }
  }
}