Series Creation

Good Day

I am fairly new to Demantra and would like some assistance.

I am trying to create a series in demantra that defaults from the Consensus Forecast. So in my little Experience the Series should be simple and should just be a server expression that looks a little like this

"sum(branch_data. fcst_consensus *#UNIT#)"

however when I save it. It gives me a validation error that says  "Server Expression Not Valid".

I am not sure what the issue here is.

Just a little more Detail. The Series is a non Editable Field and it is writing to the Sales Data Table on the Database