Hello,
Thank you for contacting Rank Math and bringing your concern to our attention.
By default, WordPress redirects the previous permalink structure to the new post URLs with category.
Unfortunately, Rank Math’s redirection cannot redirect them using a single redirect. The Regex redirect could have been used if the redirection was the other way around:
https://rankmath.com/kb/how-to-use-regex-redirects/
Looking forward to helping you.
“By default, WordPress redirects the previous permalink structure to the new post URLs with category.”
I don’t think so because this is not happening.
Hello,
Sometimes, WordPress fails to apply the redirection especially if the permalink cache is in play. In this case, you would need to create a redirection for it manually as suggested by my colleague previously.
Hope that helps and please do not hesitate to let us know if you need my assistance with anything else.
Hello,
Since we did not hear back from you for 15 days, we are assuming that you found the solution. We are closing this support ticket.
If you still need assistance or any other help, please feel free to open a new support ticket, and we will be more than happy to assist.
Thank you.
