htaccess modify vbseo_sitemap

[Emad ELsayed]

Dears
I have a vbseo_sitemap product
I want to add htaccess code in the homepage htaccess file.
RewriteEngine On
RewriteRule ^((urllist|sitemap).*\.(xml|txt)(\.gz)?)$ vbseo_sitemap/vbseo_getsitemap.php?sitemap=$1 [L]
how can I do that

[Paul M]

Edit the file and add it ?

Am I missing some issue here ?