Getting 'Unauthorized' Result from Azure OpenAI Embeddings API

Question

I have the following code that returns 'Unauthorized'. I am puzzled. Identical code with OpenAI Key (not Azure) and OpenAI URL produce 200 results. What am I doing wrong? The only thing is: Am I authorized to place a call from West US (California) to something that is designated as Location: East US...

I verified that the Api Key is correct and that the model 'ada2' is deployed:

I verified that request object looks good and consists of 'model' which is text-embedding-ada-002 and 'input' = "I am so excited to do some research..."

I also verified that URL is correct:

https://AzureOpenAIExperiment.openai.azure.com/openai/deployments/ada2/embeddings?api-version=2023-05-15

where AzureOpenAIExperiment is the resource name:

                string apiKey = config.SafeStorage.DecryptString(webSvc.ApiKey); 
                HttpClient client = new HttpClient();
                client.DefaultRequestHeaders.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Bearer", apiKey);
                client.DefaultRequestHeaders.Add("User-Agent", "GSSLLC");

                ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;
                ServicePointManager.ServerCertificateValidationCallback = delegate { return true; };

                Log.VerboseFormat("Calling PostAsync with URL: {0}, and Engine: {1}", Url, request.model);

                string jsonContent = JsonConvert.SerializeObject(request, new JsonSerializerSettings() { NullValueHandling = NullValueHandling.Ignore });
                var stringContent = new StringContent(jsonContent, UnicodeEncoding.UTF8, "application/json");

                // This runs in a separate pool thread
                Task<HttpResponseMessage> resp = Task.Run(() => client.PostAsync(Url, stringContent));
                resp.Wait();

                HttpResponseMessage response = resp.Result;
                if (response.StatusCode == HttpStatusCode.OK)
                {
                    Log.Verbose("OK");
                }
                else
                {
                    Log.Verbose(response.StatusCode);
                }