When enter web site adress, being redirected to/wp-signup.php?new=sitename.com

Hi there,

I have problem on my site. When I am enter site address to my browser I am being redirected to http://www.theblogger.com.au/wp-signup.php?new=theblogger.com.au
I have found code line on wp-signup.pho
" if ( !is_multisite() ) {
wp_redirect( site_url('wp-login.php?action=register') );

Maybe the problem is in this line ?
My web site is http://www.theblogger.com.au
Any suggestion ?
Thanks in advance!