Multiple language versions declared but no default fallback (x-default) set

On a site with several language or country versions of a page, x-default is a special hreflang value that tells search engines which version to show a visitor whose language or location does not match any of the listed alternatives. This check found that this page declares multiple hreflang alternates but no x-default fallback. Without an x-default, search engines have no instruction for what to do with visitors who fall outside the specific versions you have listed, which is the most common hreflang mistake and a frequent cause of visitors being served the wrong country's version of a page. Your developer should add an x-default hreflang entry pointing at the version you want shown to everyone else, typically your main or English-language page. This is a small addition to existing hreflang code, usually under an hour to implement and verify.