SharePoint Get List Item return "Client.FieldUserValue"

Good afternoon,

First of all, we are using SharePoint activity 1.4.2.0 and cannot be updated for organization reasons.
I am using Get List Item activity to retrieve list items from SharePoint. Everything works except the Created By field which is a person’s name containing his email address.

The value of Created by was “Client.FieldUserValue” so I tried to use a Invokecode to read the field in XML format - this XML only contains a lookupID instead of the person’s name or email.

Author:Microsoft.SharePoint.Client.FieldUserValue

“Author:<?xml version=\"1.0\" encoding=\"utf-16\"?>\r\n<FieldUserValue xmlns:xsi=“http://www.w3.org/2001/XMLSchema-instance” xmlns:xsd=“XML Schema”>\r\n 1019\r\n”
I have tried the way from below link in this forum and was no lucky. Any other suggestions? How can I get the Author’s name
instead of ID?
Many thanks!
HA
how-to-get-lookupid-in-sharepoint-list/145374