.net core 2.0 Azure AD Login Failing: AADSTS70001: Application with identifier 'xxx....' was not found in the directory 'xxxx....' - azure-active-directory

Question

Im trying to ad Azure AD login to my mvc web app. I have a web app already in azure and im trying to use an already established AD so that only them can connect to it.
I want to try it locally first.
I followed a tutorial on pluralsight and on msdn aswell, but when I start the application it gives me the error from the headline on this post in microsoft.com.
If I start the app in incognito mode I get to input my mail, which prompts a logo from the right Active Directory on the password input. After passing the password I get the same error as the headline again.
So it seems I atleast connect to the right AD.
I will post some pictures of the code and Azure, hope you can help!
I have registered my web app on the Active Directory and the registered web app properties looks like this.
and the replyUrl:
then in the web app itself, in its authentication blade:
and if you click active directory there:
This is my Configure Services in Startup
services.AddAuthentication(options =>
{
options.DefaultChallengeScheme = OpenIdConnectDefaults.AuthenticationScheme;
options.DefaultSignInScheme = CookieAuthenticationDefaults.AuthenticationScheme;
options.DefaultAuthenticateScheme = CookieAuthenticationDefaults.AuthenticationScheme;
})
.AddOpenIdConnect(options =>
{
options.Authority = "https://login.microsoftonline.com/XXXXXXXX.onmicrosoft.com";
options.ClientId = "9174eb75-18eb-4857-86aa-XXXXXXXXX";
options.ResponseType = OpenIdConnectResponseType.IdToken;
options.CallbackPath = "/auth/signin-callback";
options.SignedOutRedirectUri = "https://localhost:44386/";
})
.AddCookie();

Answer 1

According to my understanding, you want to configure Azure App Service app to use Azure Active Directory login. You should register your web app in Azure AD. Then add Azure Active Directory information to Azure App Service app. For more details, please refer to the official document.
Besides, if you want to try it in locally, you only should register your local web app in Azure AD. You do not need to add Azure Active Directory information to Azure App Service app. There is a sample for you.