I have a report that was working fine. The visuals had a forecasting line that worked fine as well. I moved the files into another folder and got expected errors regarding file location. I fixed these, however the visual with forecasting still wouldn't work. I deleted the visual started from scratch and getting it to display the correct data (without forecasting line), however, when I try and add the forecasting line I get the error message below.
Any help would be greatly appreciated. If you'd like any more information I happy to provide.