Spigot Scheduler | scheduleSnycRepeatingTask :/

[OnyxException]

Red Message: "Cannot resolve method 'scheduleSyncRepeatingTask(me.onyxzium.spigot.Main, anoymous java.lang.Runnable, long"

public void joinSchedule(final Player player) {
        BukkitScheduler scheduler = getServer().getScheduler();
        scheduler.scheduleSyncRepeatingTask(this,new Runnable() {
            public void run() {
                for (Player all : Bukkit.getOnlinePlayers()) {
                    TitleAPI.sendTabTitle(player, Main.messageData.get("tablistHeader"),Main.messageData.get("tablistFooter"));
                }
            }
        }, 20L);
    }