diff --git a/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/2F/Engines/Default.pm b/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/2F/Engines/Default.pm
index de5b8673a..379ff8d79 100644
--- a/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/2F/Engines/Default.pm
+++ b/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/2F/Engines/Default.pm
@@ -492,11 +492,14 @@ sub _displayRegister {
           unless $m;
         return $self->p->sendError( $req, 'Registration not authorized', 403 )
           unless $m->{r}->( $req, $req->userData );
+        my $prefix = $m->{m}->prefix;
         return $self->p->sendHtml(
             $req,
             $m->{m}->template,
             params => {
                 MAIN_LOGO => $self->conf->{portalMainLogo},
+                PREFIX    => $prefix,
+                "PREFIX_$prefix" => 1,
                 LANGS     => $self->conf->{showLanguages},
                 MSG       => $self->canUpdateSfa($req) || $m->{m}->welcome,
                 ALERT => ( $self->canUpdateSfa($req) ? 'warning' : 'positive' ),
diff --git a/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/Lib/Code2F.pm b/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/Lib/Code2F.pm
index 798c7bb4b..e633715aa 100644
--- a/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/Lib/Code2F.pm
+++ b/lemonldap-ng-portal/lib/Lemonldap/NG/Portal/Lib/Code2F.pm
@@ -174,13 +174,15 @@ sub sendCodeForm {
       if $stayconnected;
 
     # Prepare form
+    my $prefix = $self->prefix;
     return $self->p->sendHtml(
         $req,
         'ext2fcheck',
         params => {
             MAIN_LOGO => $self->conf->{portalMainLogo},
             SKIN      => $self->p->getSkin($req),
-            PREFIX    => $self->prefix,
+            "PREFIX_$prefix" => 1,
+            PREFIX    => $prefix,
             (
                 $self->resend_interval
                 ? ( RESENDTARGET => '/'