Hello,
Thank you for contacting the support.
We have merged your accounts as requested under the email address web******@it*****.za.
Please check on your end if everything is working as expected.
Please go through this video tutorial that shows you how to get started with your Business license:
Steps to be followed:
1. Ensure that you are logged in to your paid account
https://rankmath.com/my-account/edit-account/

2. Disconnect and reconnect your account from inside WordPress:

WordPress Dashboard > Rank Math > Dashboard > Help and click the connect/disconnect and then the connect button.
You will be taken to RankMath.com again where you can connect your account to activate your license.
You do not need to remove the free version of the plugin. Everything will be ported over to the PRO version.
Hope this helps.
Thank you.
Hello,
You are always welcome. If you have any other questions in the future, know that we are here to help you.
If you don’t mind me 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 do 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.