Validation of profile with External Terminology server

[pritam malunjkar]

below is my code to validate the profile.

I provided external terminology server link., but it is still not validating against it.

Plz help

 var client = new FhirClient("https://tx.fhir.org/r4/");
                    var svc = new ExternalTerminologyService(client);                  
                   
                    IResourceResolver resolver = new CachedResolver(new MultiResolver(ZipSource.CreateValidationSource(), new DirectorySource(profiledirectory, new DirectorySourceSettings()
                    {
                        IncludeSubDirectories = true,
                    })
                    ));
                    ValidationSettings settings = new ValidationSettings()
                    {
                        ResourceResolver = resolver,
                        TerminologyService = svc,
                    };
                    Validator validator = new Validator(settings);