DataTables warning (table id = 'referrals'): Requested unknown parameter {mData function} from the d

I am receiving a warning popup: DataTables warning (table id = 'referrals'): Requested unknown parameter {mData function} from the data source for row 0

After I dismiss the alert, the table renders as expected.

I do not know where the issue lies.

Here is the Datatables debugger: http://debug.datatables.net/akiqiy