configurationsessions

I am working on getting the configuration for configApps Feature flags. I am making the following call in c#

		var client = new HttpClient();
		var url = new Uri("https://us-west-1.console.aws.amazon.com/systems-manager/appconfig/configurationsessions");  // url to make post request to
		var json = "{ApplicationIdentifier: ddeded, ConfigurationProfileIdentifier: deded, EnvironmentIdentifier: deded}";  // json to post

		// create string content with MediaTypeHeaderValue
		var stringContent = new StringContent(json)
		{
			Headers =
			  {
				ContentType = new MediaTypeHeaderValue("application/json")
				
			  }
		};
		
		// make http request
		var response = await client.PostAsync(url, stringContent);

I am getting the 200 OK status , however I am not receiving the Token which I need for getting the configuration values.