Timer in Articulate Storyline

var player = GetPlayer();
var totalMinutes = player.GetVar("SlTimer");
var totalTimeInSeconds = totalMinutes * 60;
if (typeof window.timerInterval === 'undefined') {
    function startCountdown() {
        window.timerInterval = setInterval(function() {
            var minutes = Math.floor(totalTimeInSeconds / 60);
            var seconds = totalTimeInSeconds % 60;
            var formattedMinutes = minutes < 10 ? "0" + minutes : minutes;
            var formattedSeconds = seconds < 10 ? "0" + seconds : seconds;
            player.SetVar("TimerCount", formattedMinutes + ":" + formattedSeconds);
            totalTimeInSeconds--;
            if (totalTimeInSeconds < 0) {
                clearInterval(window.timerInterval);
                delete window.timerInterval;
                player.SetVar("TimerEnable",false)
            }
        }, 1000);
    }
    startCountdown();
}