I am trying to pre select a value within a select field in my contact from on the contact page from another page by passing a query string `?request=call-back`. I am using Ninja Forms and the values that I have in my select field are: email-us, call-back

I have tried the following:

```
add_filter( 'ninja_forms_render_default_value', 'my_ninja_forms_pre_populate', 10, 3 );
function my_ninja_forms_pre_populate( $default_value, $field_type, $field_settings ){
    if( 'request' == $field_settings[ 'key' ] ){
        $default_value = $_GET['request'];
    }
    return $default_value;
}

```

I would like the select field to have call-back already selected.