You have entered an invalid forecast name value

When I am loading data into MRP_FORECAST_INTERFACE, it is throwing an error 'You have entered an invalid forecast name value'.

I have defined a Forecast Set  'AR-FCST' already in EBS>Planner>Forecast>Sets and passing that value and trying to populate new Forecasts based on buckets.

Please advise.

t_forecast_interface_tab(v_seq).inventory_item_id := rec_fo.inventory_item_id;

       t_forecast_interface_tab(v_seq).transaction_id := rec_fo.transaction_id; --update control , if not implement is insert

       t_forecast_interface_tab(v_seq).forecast_designator := rec_fo.forecast_designator;

       t_forecast_interface_tab(v_seq).organization_id := rec_fo.organization_id;