When I try to get comments via GETrequest, I take error message which is below. By the way application's Client Status is Sandbox Mode.
P.S: My access token is working. I can understand that by changing the token so api returns invalid token message.
Pure Instagram Media
https://www.instagram.com/p/BMQjQQggJkH/
Get API
https://api.instagram.com/v1/media/BMQjQQggJkH/comments?access_token=my_token
Output
{"meta": {"error_type": "APINotFoundError", "error_message": "invalid media id", "code": 400}}