Instagram: Graph API does not return id of user who commented - facebook-graph-api

Question

I am using Facebook Graph v7.0 to access Instagram data.
I can get comments made on instagram media using the following query:
Request:
https://graph.facebook.com/v7.0/18132613492054980?fields=id,ig_id,caption,timestamp,owner,username,media_type,permalink,children,comments.limit(100){hidden,id,like_count,media,text,timestamp,user,username},comments_count&access_token
Response:
{
"id": "18132613492054980",
"ig_id": "2263043983231761272",
"caption": "Sprite",
"timestamp": "2020-03-12T06:51:27+0000",
"owner": {
"id": "17841430463493290"
},
"username": "jobyjohn123456",
"media_type": "IMAGE",
"permalink": "https://www.instagram.com/p/B9n8oM7nTt4/",
"comments": {
"data": [
{
"hidden": false,
"id": "18132938077057326",
"like_count": 0,
"media": {
"id": "18132613492054980"
},
"text": "Nice sprite \u0040yziaf__07",
"timestamp": "2020-03-12T06:52:27+0000",
"username": "zimba_birbal"
}
]
},
"comments_count": 2
}
In the response, I do not get the User Id of user who commented. It just includes the username of the commenter.
Though, I pass user in the query, the result does not include it.
Do I need any special permission to get user id of the user who commented in the comment response?

Answer 1

There is Facebook API "business discovery" to get the user details of other Instagram User.
API request:
https://graph.facebook.com/178430463490?fields=business_discovery.username(user_name_you_wantto_get_its_IgUserId){followers_count,media_count,username,ig_id}
Response:
We can pass the user name in that API request, then we will get the Instagram User Id.
The documentation says it has one limitation, this will not work for "age-gated Instagram Business IG Users" but I do not exactly know what it means. When I tested for both older Instagram account and new Instagram account (just recently created account) and this API is returning data for both.
When I tested for private Instagram account, it did not work so it seems this api works only for business account.
If that api does not work, there is one workaround. The following request help to get User Id using its username but I have not found any API documentation regarding this API. It looks like this is not a standard API and moreover it does not need any token.
https://www.instagram.com/user_name_you_wantto_get_its_IgUserId/?__a=1