Good evening

I’m trying to do an .htaccess with a rewrite url

basically the “short link” will be

mysite.it/I-123456

and it must go to

mysite.it/join.php?invitation=123456

This is the part of the .htaccess involving it

RewriteEngine On
RewriteRule ^I-([0-9]+)$ join.php?invitation=$1 [NC]

but if I type www.mysite.it/I-123456 I will still landing in the homepage…

this is the full .htaccess file

RewriteEngine On
RewriteCond %{HTTP_POST} !www.mysite.it$
RewriteRule (.*) http://www.mysite.it/$1 [R=301,L]

RewriteEngine On
RewriteRule ^I-([0-9]+)$ join.php?invitation=$1 [NC]

RewriteEngine On
RewriteCond %{HTTP_REFERER} !^$
RewriteCond %{HTTP_REFERER} !^http(s)?://(www.)?mysite.it[NC]
RewriteRule .(jpg|jpeg|png|gif|bmp|php|css)$ - [NC,F,L]

Options -Indexes

what I’m doing wrong?