Plugin redirects to cache folder gzip file

Recently I added below script into .htaccess file to prefix www. before domain.com if not found.

<IfModule mod_rewrite.c>
   RewriteCond %{HTTPS} !=on
   RewriteCond %{HTTP_HOST} !^www\..+$ [NC]
   RewriteRule ^ https://www.%{HTTP_HOST}%{REQUEST_URI} [R=301,L]
</IfModule> 

When I did this and visited floship.com, it redirected me to https://www.floship.com/wp-content/cache/page_enhanced/www.floship.com/_index.html_gzip

I cleared the cache and problem was fixed but today when I visited floship.com same problem occurred.

I don’t know why this is happens and how to fix this.

Should I use below script to fix this ?

Redirect 301 https://floship.com https://www.floship.com

I have another problem regarding background images used inside CSS files after minify. As the CSS files have relative path of images and after minify the new path is completely wrong. There is one option Never minify the following CSS files: to fix this but I want to minify the files too as they are very large in size. Currently I have overwritten the path of image.

Please help me with these two issues.