Hello,
Thank you for contacting Rank Math and bringing your concern to our attention.
We have a detailed guide on how to migrate from Yoast to Rank Math that you can follow to ensure that the data you have will be completely transferred:
https://rankmath.com/kb/yoast-seo-migration/
If you experience any issues in the process like an empty sitemap, you can get in touch with us anytime so we can investigate the issue and provide a resolution.
I hope that helps.
Thank you.
Hello,
We are super happy that we have addressed your concern. If you have any other questions in the future, know that we are here to help you.
If you don’t mind us asking, could you please leave us a review (if you haven’t already) on https://wordpress.org/support/plugin/seo-by-rank-math/reviews/#new-post about your overall experience with Rank Math? We appreciate your time and patience.
If you have another question in the future, please feel free to create a new forum topic, and it will be our pleasure to assist you again.
Thank you.