Can't get Code from Azure Active Directory from Post because of redirect

Question

I need assistance with a company website I'm working on that should be linked up with Azure Active Directory. I have read those Azure Active Directory Docs. Our cloud team have already setup Azure Active Directory on the Azure Portal and when users including myself try to access the page they are brought to a Microsoft Login Page. Our cloud team have fulfilled Step 1 of registering our app on Azure. And this process of logging into Microsoft fulfills Step 2 of Authorization. The problem here is although the users are able to sign in through Azure active directory, once they sign in and come back to the webpage, we are unable to get the code that Azure generates.

This example Authorize link from the docs shows me the correct process for authorization.

https://login.microsoftonline.com/common/oauth2/v2.0/authorize?client_id=6731de76-14a6-49ae-97bc-6eba6914391e&response_type=code&redirect_uri=http%3A%2F%2Flocalhost%2Fmyapp%2F&response_mode=query&scope=offline_access%20user.read%20mail.read&state=12345

This link will send you to Microsoft Login page and then after you sign in, it will redirect to the specified redirect_url and it will provide the code in the query parameters. I can see it in the URL bar.

My company's app authentication currently doesn't work like this. We are able to have the user sign in and get redirect back to our page. But the redirect_url for our app is www.ourwebsite.azuresites.com/.auth/login/aad/callback I haven't seen this in any other examples and I'm not sure if this is calling a Azure Active Directory specific callback through this endpoint or if somehow the app server should be handling this.

I can see through Chrome Dev Tools when this happens it is sending a post request to www.ourwebsite.azuresites.com/.auth/login/aad/callback and I can see the payload contains the code that I need but the webpage redirects immediately after that request. I have tried to setup a controller with our .Net ASP.NET backend to handle paths from /.auth/login/aad/callback by trying to send a string response back but it doesn't appear that that works.

My Major question is does the url www.ourwebsite.azuresites.com/.auth/login/aad/callback call an azure specific callback function that our app can't interact with? Or is it sending a post request to our server that we should be handling.

After we get this code we will be able to follow the rest of the authentication process.

This picture shows the initial callback call after a user logs into the Microsoft Login page and gets redirect to the www.ourwebsite.azuresites.com/.auth/login/aad/callback I can see in the dev tools that this post request contains the code.

I'm thinking that it's probably something we need to handle on the server especially since it's a post request. Regardless, any help would be appreciated!