Adding new lines to .htaccess breaks the whole site - wordpress

Question

I have an issue that when I add a simple line to the .htaccess file it immediately gives me an internal server error. I have no idead what is wrong, the current content of the .htaccess file is the following:
# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>
# END WordPress
If I add a line and get the .htaccess file looking like below, it immediately breaks the site and gives me 500 Internal server error:
# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>
# END WordPress
#Begin security
<files wp-config.php>
order allow,deny
deny from all
</files>
Could you kindly let me know what I can check in order to stop this from happening?
Another thing which I also noticed is that if I add a security plugin through wordpress, and start enabling things, it also breaks the site.
I have also looked in the error log when trying to load the site and the following is the error I get:
.htaccess: order not allowed here

Answer 1

I have fixed the issue, what I noticed is that the following configuration in my directory was blocking the .htaccess to work
AllowOverride FileInfo Options
Changed it to the following and everything
AllowOverride All