.htaccess - htaccess non www to www and remove subdomain www -

so i've got following rewrite code in htaccess

rewriteengine on rewritecond %{http_host} ^[^.]+\.[^.]+$ rewriterule ^(.*)$ http://www.%{http_host}/$1 [l,r=301]  // rewriteengine on rewritecond %{http_host} ^www\.([^\.]*)\.domain\.com$ [nc] rewriterule (.*) http://%1.domain.com$1 [r=301,l] 

works perfect redirecting non-www www domains.

i've got subdomain, lets call 'sub.domain.com' works find. if goto www.sub.domain.com, redirecting 'sub.domain.com/sub/' having idea why?

none of rules have in question routes requests subdomain's folder. /sub/ should never there if wasn't in request.

that said, of redirect rules need come before routing rules. routing rules being stuff internally routes requests other uri's, example:

rewritecond %{http_host} ([^\.]*)\.domain\.com$ [nc] rewriterule (.*) /%1/$1 [l] 

that rule internall routes folder named same thing subdomain. if rule before redirect, both rules applied , redirected uri becomes /sub/. need routing rules placed after redirect rules, e.g. rules have http:// or r flag.