Support Central

Hi karenwin,
You can go to the Backend > Systems > Template Styles > Ja Symphony - Default > Layout settings > Header then edit the block,
you can override this code to the header block:

<!-- HEADER BLOCK -->
<header id="t4-header-wrap" class="t4-header">
  <div class="t4-header-inner">
    <div class="row no-gutters">
      <div class="col-6 col-lg-4">
        <jdoc:include type="element" name="logo" />
      </div>

      <div class="col-auto d-lg-block col-lg-6">
        <div class="t4-navbar">
          <jdoc:include type="element" name="megamenu" />
        </div>
      </div>
      
      <div class="col-6 col-lg-2 t4-social d-flex justify-content-end">
        <div class="d-none d-md-block">
          <jdoc:include type="modules" name="social" />
        </div>
        <div class="languages">
          <jdoc:include type="modules" name="languages" />
        </div>
        <jdoc:include type="element" name="offcanvas-toggle" />

        <button class="navbar-toggler d-none" type="button" data-toggle="collapse" data-target="#t4-megamenu" aria-controls="t4Megamenu" aria-expanded="false" aria-label="Toggle navigation">
          <span class="toggle-bars"></span>
        </button>
      </div>
    </div>
  </div>
</header>
<!-- // HEADER BLOCK -->

And You can add the following CSS code to Tools > Custom CSS:

.navbar-brand.logo-image img {
      max-height: 100px;
      width: 230px;
} 

If you still face this issue, you can send me the admin account, I will help you check and fix this issue.
Hope this helps!