Getting exception error on 3.0.38

[lesaff]

Hi, I am getting this exception error

Exception: Method WireMailBranding::hookMethodInlineCSS does not exist or is not callable in this context (in /Users/rudy/Sites/**********/public/wire/core/Wire.php line 416)

I am running PW 3.0.38
I am calling WireMail via function in my module class like this

    public static function sendRegistrationConfirmation($params = array())
    {

        // Initiate WireMail
        $mail = new WireMail();

        $mail->header('X-Mailer', 'Sendgrid'); 
        $mail->to($params['to']);
        $mail->from($params['from']);
        $mail->subject($params['subject']);
        $mail->bodyHTML($params['body']);
        $mail->inlineCSS("wrapper");
        $mail->template("/site/templates/email/" . $params['template']);

        // Send email confirmation
        $numSent = $mail->send();

        // Write successful task to log
        $email = $params['to'];
        $log = wire("log");
        $log->save("memberships_module", "Email confirmation has been sent to $email");

    }

Thanks!