private void MatchByInvoiceNumbers(Payment payment, List <string> extractedInvoiceNumbers) { if (!extractedInvoiceNumbers.IsNullOrEmpty()) { List <string> remainingInvoiceNumbers = payment.PairExtractedInvoiceNumbers(extractedInvoiceNumbers); if (!remainingInvoiceNumbers.IsNullOrEmpty()) { List <Invoice> remainingInvoices = myFacade.Invoices.Where(_ => remainingInvoiceNumbers.Contains(_.InvoiceNumber)).ToList(); if (!remainingInvoices.IsNullOrEmpty()) { payment.AddInvoicesForUnmatchedCustomer(remainingInvoices); } } } }