Problem with croq query on category page, query not returning any results. Seeking help and suggestions.

  const query = groq`*[_type == "article" && references("category", "categories[]->slug", "${slug}")] {
    ...,
    categories[]-> {
      title,
      slug
    }  
  }

references("category", "categories[]->slug", $slug)

*[_type == "article" && categories[]->slug match $slug]{
  title,
  "slug": categories[]->slug,
}