Header rule question for Matching number string and manipulating

Acme Packet 4600 SCZ9.0.0 Patch 6 (Build 449)

Oracle Linux branches-7/el7-u9 {2022-07-21T07:00:00+0000}

Build Date=11/18/22

Question: I need help figuring out this header manipulation. The requirement is to match 7777<11digits> in RequestURI and strip 7777 from the front. I have working regex to match and new value but when I insert them into SBC it shows error.

Here is header-rule that I am working with.

 header-rule

        name                  requesturi

        header-name               request-uri

        action                 manipulate

        comparison-type             case-sensitive

        msg-type                request

        methods

        match-value

        new-value

        element-rule

            name                  requesthost

            parameter-name

            type                  uri-host

            action                 replace

            match-val-type             any

            comparison-type             case-sensitive

            match-value

            new-value                $REMOTE_IP

        element-rule

            name                  changeuriuser

            parameter-name

            type                  uri-user