This is happning just of .htaccess file
if i change the url structure without .htaccess file then it is working fine
DirectoryIndex index.php
<IfModule mod_rewrite.c>
RewriteEngine On
#RewriteBase
RewriteCond %{REQUEST_URI} ^(.*)//(.*)$
RewriteRule . %1/%2 [R=301,L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^.*$ index.php?qa-rewrite=$0&%{QUERY_STRING} [L]
RewriteCond %{HTTP_HOST} ^www\.(.*)$ [NC]
RewriteRule ^(.*)$ http://%1/$1 [R=301,L]
</IfModule>
what's wrong with it