Multi step slider doesn’t work

I tried to create a multi step slider, I followed the video tutorial but unfortunately it doesn’t work.
This is the code created

<div class="container cf7sg-slider">
  <div class="row">
    <div class="columns full cf7sg-slider-section" data-next="Next" data-prev="Prev" data-submit="Submit" data-dots="false">
      <div class="container cf7sg-collapsible" id="cf7-sg-tab-1648032332693">
        <div class="cf7sg-collapsible-title"><span class="cf7sg-title">test 1</span></div>
        <div class="row">
          <div class="columns full">
            <div class="field number"><label></label>[number number-714]
              <p class="info-tip"></p>
            </div>
          </div>
        </div>
      </div>
      <div class="container cf7sg-collapsible" id="PGTNY5">
        <div class="cf7sg-collapsible-title"><span class="cf7sg-title">test 2</span></div>
        <div class="row">
          <div class="columns full">
            <div class="field number"><label></label>[number number-714]
              <p class="info-tip"></p>
            </div>
          </div>
        </div>
      </div>
      <div class="container cf7sg-collapsible" id="E53ovF">
        <div class="cf7sg-collapsible-title"><span class="cf7sg-title">test 3</span></div>
        <div class="row">
          <div class="columns full">
            <div class="field number"><label></label>[number number-714]
              <p class="info-tip"></p>
            </div>
          </div>
        </div>
      </div>
    </div>
  </div>
</div>

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