How to ensure a Javascript code for timer with auto-advancing function works only in one block?

My survey has a Quiz section and a questionnaire section. The Quiz section is 1 block with several pages. I wanted to set a timer only in the Quiz block with an auto-advancing function.
I followed the steps and Javascript found in a discussion post (https://www.qualtrics.com/community/discussion/7656/how-to-implement-a-time-limit-at-the-block-level-plus-auto-advancing). I inserted the Javascript in the first question of my Quiz block. The timer and auto-advance function work perfectly fine.

But the problem is, the Timer count-down continues even after the Quiz block. It means if someone finishes the quiz earlier than the time limit, still the count-down continues to show up in all the following questionnaire blocks. Therefore when the time is up, the page auto-advances during the questionnaire block. To prevent this, I insert a force response feature to most of the questions in my questionnaire block. However, due to some display logic, I cannot put force responses to all the questions. Therefore there is a risk of losing answers in the questionnaire block.

The Javascript I used is provided below. I wonder what I should do to make sure that the timer and auto-advance function works only in the Quiz block, not across all the following blocks? I do not have any knowledge of programming. If someone can kindly suggest any solutions that would be a great help!



Qualtrics.SurveyEngine.addOnload(function()
{
var header = document.createElement("div");
header.className = "header"
header.id = "header_1";

var timer = document.createElement("div");
timer.className = "timer";
timer.id = "timer_1";
timer.innerHTML = "Time Remaining: <span id='time'>00:10</span>";

header.appendChild(timer);
document.body.insertBefore(header, document.body.firstChild);

function startTimer(duration, display) {
var timer = duration, minutes, seconds;
var myTimer = setInterval(function() {
Qualtrics.SurveyEngine.setEmbeddedData('timeRemaining', timer);
minutes = parseInt(timer / 60, 10)
seconds = parseInt(timer % 60, 10);
minutes = minutes < 10 ? "0" + minutes : minutes;
seconds = seconds < 10 ? "0" + seconds : seconds;
var text = ('innerText' in display)? 'innerText' : 'textContent';
display[text] = minutes + ":" + seconds;

if (--timer < 0) {
clearInterval(myTimer);
timeOver();
}
}, 1000);
}
var timerSeconds = parseInt("${e://Field/timeRemaining}");
display = document.querySelector('#time');
startTimer(timerSeconds, display);
var timeOver = function() {
document.getElementById("timer_1").innerHTML = "Time is up.";

$('NextButton').click();
}
});