diff --git a/src/order/ShowOrder.js b/src/order/ShowOrder.js
index dbafbd74f8418d27916f4f504e507d4748e0feef..222a47768d6c6606496f0c2619986edf2497f8f0 100644
--- a/src/order/ShowOrder.js
+++ b/src/order/ShowOrder.js
@@ -29,7 +29,7 @@ function ShowOrderResults(props) {
   const transactions = props.order.transactions.map((t) => {
     const list = t.order_purchase.map((purchase) => {
       const i = products.findIndex((p) => p.code === purchase.product_code);
-      if (!i) {
+      if (i === -1) {
         return null;
       }
       products[i].amount += purchase.amount;