Copying Function Modules

Hi there, newbie ABAP er here,

I want to reset the SENDER value in FM SO_NEW_DOCUMENT_ATT_SEND_API1 from SPACE to a valid non-reply email address. Obviously I dont want to alter the Function module so I made a Z copy in my ZDEV package -> Function group -> Function module.

Seeing as the original FM was in Function group SOI1 I'm getting an error as various statements in the FM are tripping out as they are macros within SOI1 and probably cant be seen.

Can anyone advise the right way of cracking this?