Why are the twitter and og (OpenGraph) not rendering cards link on social networks?

I have added social <meta /> for twitter and og (OpenGraph) on this Web page:

https://app.testing.passculture.team/offre/224359

These are present in the head of the page and added by react-helmet:

    <meta name="twitter:card" content="summary" />
    <meta name="twitter:site" content="@nytimesbits" />
    <meta name="twitter:creator" content="@nickbilton" />
    <meta
      property="og:url"
      content="http://bits.blogs.nytimes.com/2011/12/08/a-twitter-for-my-sister/"
    />
    <meta property="og:title" content="A Twitter for My Sister" />
    <meta
      property="og:description"
      content="In the early days, Twitter grew so quickly that it was almost impossible to add new features because engineers spent their time trying to keep the rocket ship from stalling."
    />
    <meta
      property="og:image"
      content="http://graphics8.nytimes.com/images/2011/12/08/technology/bits-newtwitter/bits-newtwitter-tmagArticle.jpg"
    />

This snippet is a copy/past from the Twitter documentation: https://developer.twitter.com/en/docs/twitter-for-websites/cards/guides/getting-started#twitter-cards-and-open-graph

Why are the metas not read nor used for creating card links when shared on social networks such as Twitter, Facebook, WhatsApp?

I use a GCP bucket and by default, index.html Content-Type: text/html is already set. The validator here still fail to validate: WARN: No metatags found