2026-01-15 10:22:41.882 ERROR 14872 --- [http-nio-8080-exec-3] c.e.api.OrderController  : Unhandled exception
java.lang.NullPointerException: Cannot invoke "com.example.model.Customer.getEmail()" because "customer" is null
	at com.example.api.OrderService.notify(OrderService.java:142)
	at com.example.api.OrderService.placeOrder(OrderService.java:88)
	at com.example.api.OrderController.create(OrderController.java:54)
	at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
	at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:255)
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1089)
Caused by: java.lang.IllegalStateException: customer lookup returned no rows for id=4021
	at com.example.api.CustomerRepository.findById(CustomerRepository.java:67)
	... 6 more