Yoast SEO XML SItemap Error

Similar problem — sitemap not generated, get error msg:

This page contains the following errors:
error on line 4 at column 6: XML declaration allowed only at the start of the document
Below is a rendering of the page up to the first error.

[and the page below is empty]

Found solution at https://www.ads-software.com/support/topic/xml-parsing-error-xml-or-text-declaration-not-at-start-of-entity-1?replies=6

Apparently caused by blank lines outside of <? and ?> bracketed section(s) in the theme’s functions.php file

Removing the blank lines solved the problem. Many thanks to DigitalPresences

It could also be a single space after the ?> (not just a blank line) in a plugin file (not just the functions.php file)… ??

[found the solution, thanks]

Yes! Removing the spaces outside of <? and ?> in the functions.php file resolved the error message. I just made sure that every bracketed section was closed up to the one above, and the sitemaps worked. Thanks!

Ohh.. I also had this problem scene yesterday, I fixed it from this error on line 2 at column 6