Hello Everyone Can anyone help me to set tracking Number in 'package-sublist' on creating Item-Fulfillment Record. I am getting an error 'SSS_INVALID_SUBLIST_OPERATION' And when I am fetching the line count of package sublist then '-1' occured. but I think this is an issue if I am creating a new fulfillment record then how can the package sublist line count be -1, it could be 0 ? Anyone Please help

You would get a -1 if it can't find the sublist you are referencing. Maybe check spelling on the sublistId. It should be

rec.getLineCount({sublistId: 'package'});

there are carrier specific package sublists like

packageups