Format of mapping used for lookup doesn't match any dimension of the source

Hi all,

I've looked through several of the queries/answers on this topic and still can't work out what I am doing wrong...

I am trying to provide a summary of employee expenses by region and role in REP04;

I am trying to use EMP02 as my source as this has employee expenses by employee and department. As there is no direct link I was using SYS08 as a lookup link referencing the Employee role and Region (the link being through the common employee details). I get the following;

I'm clearly missing something in the logic - no idea what though...

Thanks in advance!

Emma