How to make authorization through Instagram using http requests?

Question

JavaScript

Hello, I want to make authorization in instagram through http requests. c# language. If you click on the link below, an authorization form will appear.
https://instagram.com/oauth/authorize/?client_id=1...
When authorizing, a POST request is sent with parameters:
csrfmiddlewaretoken = "the key is on the page"
username = ""
password=""
And all this is sent to:
https://instagram.com/accounts/login/?force_classi...
When I go, I get an http 403 error. I save cookies, changed the User-Agent, and there's no point.

Answer 1

Could you show me your code.
And so, if you directly vang - I think the problem is that you do not process the redirect.
There is a sequence like this, first you have to send a get request, then intercept the redirect to the form with permission to give access rights and from there send further. In the response, intercept the code that will go after your callbackurl

Answer 2

Why not use their API for this?
I don’t program in sisharp, but there are a lot of solutions on github .
I myself work with this unofficial api , based on standard methods, but this is already php.