E9.2 Revenue business unit error during sales order entry


We recently created a new branch plant. During testing, I am entering a test SO sales order. Initially, when entering the SO detail line, the revenue business unit is giving the error "Invalid Business Unit". If I click on the Revenue Business Unit column and re-enter the same value, the error goes away. I'm sure this is a setup problem, but I think I've checked everything, but I can't find a problem. We are using E1 9.2

Any thoughts on what might be causing this?