Hello,
Thank you for contacting Rank Math support, and sorry for any inconvenience that might have been caused due to that.
It seems like you purchased the plugin with some other email address.
Can you please search and forward a receipt from FastSpring.com so we can locate your account?
Also, please share the recent error log from your server with us to further check and assist you on this. If you are not sure where to look for the error log, you may contact your hosting provider.
Looking forward to helping you.
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.