In the Zoho Creator Customer Payment form i Have customer field on select of the field Data want to fetch from the invoice from based on the customer name In the Customer Payment form i Have subf

In the Zoho Creator Customer Payment form i Have customer field on select of the field Data want to fetch from the invoice from based on the customer name In the Customer Payment form i Have subf

In the Zoho Creator Customer Payment form i Have customer field on select of the field Data want to fetch from the invoice from  based on the customer name 

 In the Customer Payment form i Have  subform  update Invoice , there i have date field,Invoice number , i want to fetch that feild from invoice Duedate, invoice Date  it the main field invoice Form.

fec = Invoice[Customers_Name == input.Customer_Name];

info fec.Due_Date;

if(fec != null)

{

input.Location = fec.Location_Name;

input.Payment_Date = zoho.currentdate;

row.Date_field=fec.Due_Date;

row.Invoice_Number=fec.Invoice_Number;

}

info "Test Date" + invoice.Date_field;

The above code i used But Getting Error
Pls Help how to fix this