Show error for creating user

application/confidentialClient/src/main/java/org/fuseri/confidentialclient/AuthClientController.java

@@ -45,7 +45,7 @@ public class AuthClientController {
             var response = userRegisterRestTemplate.postForObject(url, request, UserDto.class);
             return response == null ? "Unable to create user." : response.toString();
         } catch (RestClientException e) {
-            return "Unable to create user. Is module LanguageSchool running?";
+            return "Unable to create user: " + e.getMessage();
         }
     }