How to create Azure Feature Flag for the App Configuration through c# code?

I am using .net core 3 to create configuration setting in App configuration. I was able to create a key-value in the configuration explorer using the following code snippet and some additional configuration in the link below

var client = new ConfigurationClient(_configuration.GetConnectionString("AppConnectionString"));
var settingToCreate = new ConfigurationSetting(model.Key, model.Value);
client.SetConfigurationSetting(settingToCreate);

https://github.com/Azure/azure-sdk-for-net/blob/main/sdk/appconfiguration/Azure.Data.AppConfiguration/README.md#create-a-configuration-setting

I am currently working on creating a feature flag in feature manager pane of App Configuration using the same approach but providing the contenttype for featureflag as below.

var client = new ConfigurationClient(_configuration.GetConnectionString("AppConnectionString"));
var settingToCreate = new ConfigurationSetting(model.Key, model.Value);
settingToCreate.ContentType = "application/vnd.microsoft.appconfig.ff+json;charset=utf-8";
client.SetConfigurationSetting(settingToCreate);

The issue is it creates a feature flag but without a name, showing an error message as below configuration explorer

feature manager

Please suggest any possible solutions. Thanks in advance!