Registering member - language fails

I can’t figure out where the error is in my code.
I’m trying to register a user, everything works except the language.

I write my code

userEmail =                $w("#InputMail").value;
userPassword =              $w("#InputPassword").value;

wixUsers.register(userEmail, userPassword, {
    
 contactInfo: {

 "name":         userName,   
 "firstName":    $w("#InputName").value,
 "lastName":     $w("#InputCognome").value,
 "phones":       [userTelefono],
 "labels":       ["Registrazione"],
 "language":     $w('#InputNazione').value, // write only En 
 // personal field
 "Indirizzo":    $w("#InputIndirizzo").value,
 "Citta":        $w("#InputCitta").value,
 "Cap":          $w("#InputPoste").value,
 "Provincia":    $w("#InputProvincia").value,
 "Nazione":      $w("#InputNazione").value

}
})

whatever the field value is, it always returns the “en” language.
I tried as a value of $ w (‘# InputNazione’):

“Japan”
“Jp”
“Italy”
“It”

but nothing doesn’t work.
Has anyone ever found this problem

thanks a lot

Has anyone had the same problem?

Help Pleaseeee