Filter using Entity schema query

Hello ,

i want to filter the overdue invoices and for individual account invoices. I have written following code but it is not working.

                    var esqFirstFilter = select.createColumnFilterWithParameter(Terrasoft.ComparisonType.NOT_EQUAL, "Activity.PaymentStatus" , "Paid");
                    var esqSecondFilter = select.createColumnFilterWithParameter(Terrasoft.ComparisonType.EQUALS, "Account", this.get("Id"));

Thank you.