diff --git a/packages/graphql/api/orders.ts b/packages/graphql/api/orders.ts
index c9fae88..2b2f274 100644
--- a/packages/graphql/api/orders.ts
+++ b/packages/graphql/api/orders.ts
@@ -52,10 +52,11 @@ export class OrdersService extends BaseService {
         throw new Error(ERRORS.INVALID_CLIENT);
       }
 
-      const masters = await customersService.getMasters(this.customer);
+      const { customers } = await customersService.getMasters(this.customer);
+      const masters = customers.at(0)?.masters;
 
       const masterId = slot?.master?.documentId;
-      if (!masters.customers.some((master) => master?.documentId === masterId)) {
+      if (!masters?.some((master) => master?.documentId === masterId)) {
         throw new Error(ERRORS.INVALID_MASTER);
       }
     }