Hello,
We apologize for the inconvenience you are facing with your Rank Math PRO subscription not working on your website due to a possible incorrect email address. To resolve this issue, you need to connect the correct email address to your PRO account.
If you suspect that the PRO plan is linked to the wrong email address, you can contact our support team to merge both accounts or change the email connected to your PRO plan. Please navigate to the Rank Math Support Forum and open a ticket. In the ticket, provide details about the email address you used to purchase the PRO plan or a screenshot of the invoice received from FastSpring.com.
Here is an example of how to submit a ticket with the necessary information:

Our support team will then locate your PRO account and update the email address connected to it or merge it with your FREE account as requested.
Thank you for bringing this to our attention. If you have any further questions or need assistance, feel free to reach out to our support team through the ticket you submit. We are here to help 24/7, 365 days a year.
Sources:
I Purchased Rank Math PRO but Rank Math is Still Showing FREE » Rank Math
I Purchased Rank Math PRO but Rank Math is Still Showing FREE » Rank Math
How to Fix PCLZIP_ERR_BAD_FORMAT (-10): Unable to find End of Central Dir Record signature » Rank Math
Why Should You Avoid Group Buying and Sharing Rank Math PRO Subscription? » Rank Math
How to Cancel Your Rank Math PRO Subscription » Rank Math
This is an automated reply from Rank Math Support Bot. If you need further assistance, please reply to this topic and a human support agent will reply to you shortly.
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.