Google rich snippet always shows "Sold out" for available (ld+json) offer schema

Question

We have listing menu items for the restaurant and something wrong, it always shows "Sold Out" in Google's search results. The items given to Gooogle as ld+json schema with the availability property.

Snippet part (with liquid variables from backend):

<script type="application/ld+json">
  {
    "@context": "http://schema.org",
    "@type": "Restaurant",
    "name": "{{ account.business_name | replace: '"', "'" }}",
    "description": "{{ location_description | replace: '"', "'" }}",
    "acceptsReservations": "{{ reservations_are_avalible }}",
    "url": "{{ account.website_url | replace: '"', "'" }}",
    "logo": "{{ account.logo_medium_url }}",
    "image": "{{ account.logo_medium_url }}",

    "hasMenu": [
      {% for menu in account.visible_menus %}
        {
          "@type": "Menu",
          "name": "{{ menu.name | replace: '"', "'" }}",
          "url": "{{ menu.path }}",
          "hasMenuSection": [
            {% for menu_section in menu.sections %}
              {
                "@type":"MenuSection",
                "name": "{{ menu_section.name | replace: '"', "'" }}",
                "image": "{{ account.logo_medium_url }}",
                "hasMenuItem": [
                  {% for item in menu_section.items %}
                    {
                      "@type":"MenuItem",
                      "name": "{{ item.name | replace: '"', "'" }}",
                      "description": "{{ item.description | replace: '"', "'" }}"
                      {% if item.pricepoints[0].price != blank %}
                      ,"offers": {
                         "@type": "Offer",
                         "price": "{{ item.pricepoints[0].price }}",
                         "priceCurrency": "USD",
                         "availability": "https://schema.org/InStock"
                      }
                      {% endif %}
                    }
                    {% if forloop.last == false %}
                    ,
                    {% endif %}
                  {% endfor %}
                ]
              }
              {% if forloop.last == false %}
              ,
              {% endif %}
            {% endfor %}
          ]
        }
        {% if forloop.last == false %}
        ,
        {% endif %}
      {% endfor %}
    ]
  }
</script>  

When I search the "borealis grille menu kitchener" I see each item listed as "Sold out":

UPDATE (10.24.2020):

This is the ld+json code after the page loaded with all needed properties: Pastebin

This is a test results screenshot from Google rich results testing tool:

I have 2 warnings "Missing fileds (optional)" - servesCuisine and priceRange:

As you can see the item Buttermilk Fried Chicken Tenders has "InStock" availability. But on the search results of "graffitimarket menu kitchener" it shows "Sold out":

Answer 1

What you are showing is a featured snippet. These are not typically based on structured data. They normally process the pages content and use that to put together a snippet. In this case a list of items from the menu.

Your menu items consist of a name and a price. But if you inspect the html, there is also a hidden element containing the words "Sold out". So I suspect Google is not picking up that it is hidden, and has included it.