error on line 3 at column 6: XML declaration allowed only at the start of the do

Hello,

I’m sorry to hear that you are facing an issue with your sitemap. To address the error “error on line 3 at column 6: XML declaration allowed only at the start of the do,” it seems like there might be an issue with the XML declaration in your sitemap file.

One common reason for this error is having white spaces or characters before the XML declaration in the sitemap file. This can cause parsing issues and lead to the error you mentioned.

To resolve this, you need to ensure that there are no white spaces, characters, or any content before the XML declaration in your sitemap file. The XML declaration should be at the very beginning of the file.

If you have checked the source code and confirmed that there are no extra characters or white spaces before the XML declaration, you may want to verify if there are any conflicting plugins or themes causing this issue. You can use the Health Check plugin to identify any conflicts.

If the issue persists after checking these steps, please provide more details or reply with additional information so we can further assist you in resolving this problem.

Thank you for reaching out, and we appreciate your patience as we work to resolve this issue for you.

Sources:
Rank Math Sitemap Issues and Their Fixes » Rank Math
How To Exclude Rank Math Sitemaps from Caching » Rank Math