I read the new documentation for Instagram subscriptions API. It says that after you subscribe, Instagram will notify you when people post new media on their page.
I would like to be notified when one of the user's post receive a new like or a comment?
Do you think this is possible?
The Instagram API does not currently support this option.
From the User Subscription Page:
User subscriptions are useful if you want to be notified when people who authenticated your app post new media on Instagram.
You will get a POST request only when there is a new post, it will not notify for likes or comments.