Why are my custom HTML blocks not appearing on my website?

Hello I am creating my own index_html.liquid a new one to be exact.

My goal is instead the custom html is a section I wanted it the custom part is a blocks, to make it clean in section sidebar. Because its to messy if you see lot of section Custom HTML.

The ideal a section with blocks of custom html. I already made it, but the only problem is the blocks content is not appearing on the website. ( check the image below )

I tried to circle back the code, and do some modification, and do some comparison about setup of blocks in schema in other section with blocks as well. But I don’t see a error why I dont see my block content. Even the Default placeholder it is not showing. B

Below is the code I created. The goal here is to able to work fine the blocks so that I can do start putting a code in blocks and should appear on the website.

BTW our theme is in Flex. As of now I am not using this section yet until its gonna fully working. That’s the reason why I paste the code below.

I really appreciate all your help, suggestion, and feedback.

{%- assign html_content = blocks.settings.html_content -%}
{%- assign blocks = section.blocks -%}

{% schema %}
  {
    "name": "Custom HTML",
    "class": "html-section",
    "max_blocks": 3,
    "settings": [
      {
        "type": "header",
        "content": "Layout"
      }
    ],
    "blocks": [
      {
        "type": "textarea",
        "name": "html",
        "settings": [
          {
            "type": "html",
            "id": "html_content",
            "label": "HTML",
            "default": "Place your code here"
          }
        ]
      }
    ],
    "presets": [
      {
        "name": "New Custom HTML",
        "category": "Layout",
        "settings": {
          
        }
      }
    ]
  }
  {% endschema %}