Problem: The client reported an issue with mixed language search engine results pages (SERPs) being indexed, even after setting up the Multilingual SEO Plugin and configuring meta translations. The specific problem was with a URL parameter (?lang=de) that should not exist and does not function correctly, as it displays content in the wrong language.
Solution: We recommend reaching out to the Rank Math team for assistance with the redirect issue, as it is beyond our control. Alternatively, you can seek help from a certified contractor who can set up the necessary redirect in the .htaccess file and troubleshoot why it is not working in the current server environment. Certified contractors can be found at https://wpml.org/contractors/.
In the meantime, using a redirection plugin as previously mentioned could provide a temporary fix for the problem.
