    public function contactInformationSave(Request $request) {

        $firstName = strip_tags($request->get('first_name'));
        $lastName = strip_tags($request->get('last_name'));
        $email = strip_tags($request->get('email'));
        $phone = strip_tags($request->get('phone'));

        session_append_array('checkout_v2', [
            'first_name'=> $firstName,
            'last_name'=> $lastName,
            'email'=> $email,
            'phone'=> $phone
        ]);

        $validate = $this->_validateContactInformation($request->all());
        if ($validate['valid'] == false) {
            session_set('errors', $validate['errors']);
            return redirect(route('checkout.contact_information'));
        }

        // Success
        return redirect(route('checkout.shipping_method'));
    }
The software constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.