Composer: "connecting..." for more then 5 minutes

I’m new to Pimcore. I followed the guide and try
COMPOSER_MEMORY_LIMIT=-1 composer create-project pimcore/demo my-project

But it just keep saying

Creating a “pimcore/demo” project at “./my-project”
Installing pimcore/demo (v1.4.1)

  • Installing pimcore/demo (v1.4.1): Downloading (connecting…)

I’ve tried to install other things (Yii2 because that’s what I know). And it finished within 2 minutes. So I guess it’s not my connection problem