Using is_page() results in duplicate schema

Question

I have different FAQ schema for different pages. When I test each page, the rich result test returns warning with duplicate FAQ schema. The FAQ schema is duplicated because the rich result detects the schema for other pages together with the tested page. How can I remove the duplicated schema?

My pages structure are as follow:

example.com/FAQ/page_name    
example.com/FAQ/page_name02    
example.com/FAQ/page_name03

My snippet:

add_action( 'wp_footer', function () { ?>

if ( is_page('page_name' ) ) {
<script type="application/ld+json">
{
  "@context": "https://schema.org",
  "@type": "FAQPage",
  "mainEntity": [
    {
      "@type": "Question",
      "name": "",
      "acceptedAnswer": {
        "@type": "Answer",
        "text": ""
      }
    }
  ]
}

</script>
endif;
} 

<?php } );