```csharp
public static class TimerManager
    {
        public static System.Timers.Timer aTimer;
        public static System.Timers.Timer bTimer;
        public static DateTime TimeStart { get; set; }

        public static void SetGameTimer()
        {
            SetTimerGame();
            SetTimerAlert();
        }

        private static void SetTimerGame()
        {
            // Create a timer with a two second interval.
            aTimer = new System.Timers.Timer(RedBlue.Instance.Configuration.Instance.matchTimems);
            TimeStart = DateTime.Now;
            // Hook up the Elapsed event for the timer. 
            aTimer.Elapsed += OnTimedEvent;
            aTimer.AutoReset = false;
            aTimer.Enabled = true;
        }

        private static void SetTimerAlert()
        {
            // Create a timer with a two second interval.
            aTimer = new System.Timers.Timer(1000);
            // Hook up the Elapsed event for the timer. 
            aTimer.Elapsed += OnTimedAlert;
            aTimer.AutoReset = true;
            aTimer.Enabled = true;
        }

        private static void OnTimedAlert(object sender, ElapsedEventArgs e)
        {
            TimeSpan timeLeft = DateTime.Now - TimeStart;
            foreach (SteamPlayer Steamplayer in Provider.clients)
            {
                if (timeLeft.Seconds <= 9)
                {
                    EffectManager.sendUIEffectText(34, Steamplayer.transportConnection, false, "timer", $"{timeLeft.Minutes}:0{timeLeft.Seconds}");
                }
                else
                {
                    EffectManager.sendUIEffectText(34, Steamplayer.transportConnection, false, "timer", $"{timeLeft.Minutes}:{timeLeft.Seconds}");
                }
            }
        }

        private static void OnTimedEvent(object sender, ElapsedEventArgs e)
        {
            UnturnedChat.Say("Come on guys! You need to hurry up!");
            GameManager.EndGame("No");
        }

        public static void StopGameTimer()
        {
            aTimer.Enabled = false;
            bTimer.Enabled = false;
        }
    }
```