can't get attr of some HTML

html = `"<input type=\"text\" name=\"filter_form[vndr_nbr]\" id=\"filter_form_vndr_nbr\" value=\"GFEVYWDJNT\" class=\"block w-full rounded-lg text-gray-900 read-only:border-dashed focus:ring-0 sm:text-sm sm:leading-6 border-gray-300 focus:border-primary-400\" size=\"10\" data-test-role=\"vendor-number-field\"/>"`

```
iex(4)> HtmlQuery.attr(html, "value")
nil
```