diff --git a/yajsapi/executor/index.ts b/yajsapi/executor/index.ts
index cf18c44f1..510a54306 100755
--- a/yajsapi/executor/index.ts
+++ b/yajsapi/executor/index.ts
@@ -359,7 +359,7 @@ export class Executor implements ComputationHistory {
             emit(new events.PaymentFailed({ agr_id: invoice.agreementId, reason: e.toString() }));
           }
         } else {
-          invoices.set(invoice.agreementId, invoice);
+          invoices[invoice.agreementId] = invoice;
         }
         if (payment_closing && agreements_to_pay.size === 0) {
           break;