HMR to reject 503 Unavailable when not Authorization-Header

Hi,

  What is wrong in this HMR to not reject with SIP:503 Unavailable the REGISTER request coming with "Authorization" header?

sip-manipulation

name rejectRegisterCseqAuthorization

   description

   split-headers

   join-headers

   header-rule

    name rejectRegister2

    header-name Authorization

    action manipulate

    comparison-type case-sensitive

    msg-type request

    methods REGISTER

    match-value

    new-value

    element-rule

       name Check_Auth

       parameter-name header-value

       type

       action store

       match-val-type any

       comparison-type pattern-rule

       match-value

      new-value

   header-rule

     name rejectRegister3

     header-name Authorization

     action reject

     comparison-type boolean

     msg-type request

     methods REGISTER

     match-value !$rejectRegister2.$Check_Auth

     new-value 503:"Service Unavailable"

Do you have any suggestion?

Br and thanks in advance

Alejandro