Can I edit the really simple ssl htacess line to make sure the www never shows up?

Really simple changed my htaccess file and amended/deleted the lines that forced the www.mysite.com to always redirect to mysite.com.  So, now google and bing both read both the www and the non-www page.   This is causing two issued... 1) a duplicate page which can hurt rankings; and 2) the www page never shows up as mobile friendly.  Is there a way to edit the htaccess command that Really Simple puts in to add the remove www?  ie here is your htaccess commands:

RewriteEngine on
RewriteCond %{HTTPS} !=on [NC]
RewriteRule ^(.*)$ https://%{HTTP_HOST}/$1 [R=301,L}

But, I need this to remove the www consistently:

RewriteEngine on
RewriteCond %{HTTP_HOST} ^www\.
RewriteRule ^(.*)$ http://<em>mysite.com</em>/$1 [R=301,L]

When I add those lines either above or below the ReallySimple lines, it doesn't correct the problem.  But, if I turn Really Simple off and add that rewrite rule, it works.  So, how can I keep Really Simple active, while still making sure the command for the force-no-www works?

Thank you so much!!!!