Hello,
Thanks for contacting us and we regret the inconvenience caused.
I checked your sitemap and I was able to replicate the issue. The error usually occurs when you have blank lines or white spaces in your wp-config.php file. Please refer to our tutorial guide to fix the issue: https://rankmath.com/kb/fix-sitemap-issues/#xml-text-declaration
Please let us know how that goes.
Thanks.
There are no whitespaces in my wp-config
Hello,
Thank you for keeping in touch with us.
I am trying to access your admin dashboard but Jetpack is blocking me. Can you please temporarily disable Jetpack so we can further investigate the issue?
If you want, you can use the below plugin to generate a temporary login URL to your website and share that with us instead:
https://wordpress.org/plugins/temporary-login-without-password/
You can use the above plugin in conjunction with the WP Security Audit Log to monitor what changes our staff might make on your website (if any):
https://wordpress.org/plugins/wp-security-audit-log/
We really look forward to helping you.
HI, Jetpack has been deactivated.
Hello,
Thanks for the reply.
Upon inspecting the source code of the sitemap, I noticed that a blank line (line 1) is present there. https://i.rankmath.com/b6kJSk
This is caused either when there is a blank space or line in the wp-config.php, fucntions.php file or due to a plugin-theme conflict.
We might need to take a closer look at the settings. Please edit the first post on this ticket and include your FTP logins in the designated Sensitive Data section.

It is completely secure and only our support staff has access to that section.
We really look forward to helping you.
Hello,
I have updated the sensitive data as requested. Can you please check further?
Thank you.
Hello,
Thank you for the update, and sorry for the delay.
You can follow the steps in our guide to determine which plugin is conflicting with the generation of your sitemap.
Only the site admin would know and your users won’t be affected by this troubleshooting.
The FTP credentials you have provided seem incorrect as the downloadable file is for your site’s SSL RSA private key. You can add the password and port of your FTP.
I hope that helps. Thank you, and looking forward to your update.
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.