diff --git a/src/fmg-components/cart/cart.vue b/src/fmg-components/cart/cart.vue
index 6d709edeb..28cb25d50 100644
--- a/src/fmg-components/cart/cart.vue
+++ b/src/fmg-components/cart/cart.vue
@@ -177,9 +177,9 @@ export default {
                 return [];
             }
             return [
-                ...this.lineItems.glassParts,
-                ...this.lineItems.supportingItems,
-                ...this.availableVaps,
+                ...this.lineItems.glassParts ?? [],
+                ...this.lineItems.supportingItems ?? [],
+                ...this.availableVaps ?? [],
             ];
         },
         cartItems: {