Headings in Shortcode doesn't appear in TOC Table of Content

Headings in the shortcode are not showing. Please help me fix it.

 <div class="r-s-p-b">
        {{ .TableOfContents }}
        {{ .Content | htmlUnescape | safeHTML }}
    </div>

That’s the Single code.

and here’s the shortcode heading.

{{<html-code tag="h3" class="large-font" style="text-align:center">}}2. Lenovo ThinkPad X1 Carbon{{</html-code>}}

help me fix it. please

Hi, I believe that’s a known issue, also discussed with possible workarounds here: Shortcode processing order