After you add hreflang tags, make certain they all level to indexable and crawlable pages. Check which tags are causing the problems and rectify them by ensuring that the pages they’re pointing to are Are living. Use Google’s URL inspection tool if necessary to Verify individual pages and reveal their https://www.presta-addons-modules.com/en/opencart-seo-automatic-google-rich-snippets-json-ld-integration-opengraph-twitter-tags-schemaorg.html