Report Builder - Invalid Field "Business Unit Field"

Hello!

I've created a report for a trial balance in a consolidation company that includes Business Unit, Department (dimension), Account, and balance at date. I've added a filter to the Key so that it's looking only at posting accounts and the company I want it to. I've also added date filters to the "Balance at Date" field. When I manually change the Business Unit Code field to one (to test), the field fills in perfectly. When I run the report, I get the attached error (1 is the error, 2 is what the report looks like when I click OK). I am not sure why when it goes into report mode it loses that Business Unit Code. Can anyone help, this is an urgent report requirement.

Thanks!

• Error 1.JPG
• Error 2.JPG