Problem in htaccess file, how to fix?

Question

Search Engine Optimization

Good afternoon everyone.
I am preparing my blog for going online, trying to get rid of duplicate pages.
I write a command to the htaccess file, as per instructions I add after RewriteRule ^index\.php$ - [L]:
I add:
RewriteCond %{QUERY_STRING} ^replytocom= [NC]
RewriteRule (.*) $1? [R=301,L]
RewriteRule (.+)/feed /$1 [R=301,L]
RewriteRule (.+)/attachment /$1 [R=301,L]
RewriteRule (.+)/comment-page /$1 [R=301,L]
RewriteRule (.+)/comments /$1 [R=301,L]
RewriteRule (.+)/trackback /$1 [R=301,L]
RewriteCond %{QUERY_STRING} ^attachment_id= [NC]
RewriteRule(.*) $1? [R=301,L]
I save the whole thing and close it.
After that, I add one code to the topic and that's it.
/* Inserts the noindex,nofollow robot meta tag for pagination */
function my_meta_noindex () {
if (
is_paged() //
) {echo "".''."\n";}
}
add_action('wp_head', 'my_meta_noindex ', 3); // add your noindex,nofollow to head
BUT after 5 minutes I look at the htaccess file and it's already empty, everything I added has disappeared!
I do everything through the file manager, I save everything.
What is the problem?
Just in case, maybe it's a bug?
instructions for which I did: pro-wordpress.ru/chast-2-raskrutka-bloga/kak-izbav...

Answer 1

What permissions do you have on .htaccess?
Try setting it to 600 to allow the owner to read and write, and deny everything else.

Answer 2

Don't put your instructions between the lines

# BEGIN WordPress

# END WordPress

This place is taken over by WP and does what it wants there. But outside of these lines, he does not touch anything else.

Answer 3

Check if you have installed a plugin that protects changes. Disable all plugins and check htaccess, if changes are not removed from htaccess, then everything is fine.