Hello,
Thank you for contacting us and sorry for any inconvenience that might have been caused due to this issue.
Do you mean perhaps the email you used for your Rank Math account? If that is the case, please go to:
https://rankmath.com/my-account/edit-account/
Change the current Email address to your desired one and then click the Save Changes button.

If the above is not the issue to help us understand the problem more clearly and provide a quick and smooth solution, please elaborate more on the issue you are experiencing.
Please send screenshots showing the exact problem and, if possible, a recorded screencast video demonstrating the issue.
Visual information like this can greatly assist us in pinpointing what might be going wrong.
You can use tools like Imgur for screenshots or Loom for screencasts.
We are really looking forward to helping you.
Thank you.
No, I’m not talking about changing the email, I’m talking about linking accounts. I want to change to Google between WordPress, Google, and Facebook, what should I do?
Hello,
To link your Google Account from using SSO, head over to your Google account permission and add your Google login from here: https://myaccount.google.com/permissions
You can add Rank Math from the list of signing options and then you can use your email address instead.
Hope that helps.
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.