Virtualmin roundcube password Drivers not work with error

Operating system:Debian
OS version:Jessie
Hello,

I use identifiers in the form username@domain
when I validate the password change I get the following error:
No user named "username-domain-with-dash.fr" was found in the server "domain-with-dash.fr"
The problem is that if I integrate a code of this type:
$username = escapeshellcmd(str_replace('-'.$domain, '@'.$domain, $username));
my error becomes:
No user named "username@domain@avec@tiret.fr" was found in the server "domain-with-username.fr"
I’m using the latest online version of the virtualmin drivers and Roundcube version: 1.4.11
could you try to help me?
I will be grateful to you !