Assuming customerdetails is required, the following 2 results were found.
= r_ZB_InvoiceDetails.get("invoice"); // // determine recipients l_ZB_InvoiceRecipients = List(); r_ZohoBooks_CustomerDetails = zoho.books.getRecordsByID("contacts",v_BooksOrgID,m_ZB_InvoiceDetails.get("customer_id"),"zbooks");...
to "customer_id": "123456700000001234567", get customer id then Email v_BooksCustomerID = invoice.get("customer_id"); r_CustomerDetails = zoho.books.getRecordsByID("contacts",v_BooksOrgID,v_BooksCustomerID,"zbooks"); v_CustomerCheckCode =...