Active Directory authentication for Umbraco 7.6 gets stuck in a re-direct loop - azure

Question

I am currently using an Umbraco library to extend the Authentication possibilities and enable back office authentication with Active Directory.
https://github.com/umbraco/UmbracoIdentityExtensions
After installing the library and following the blog post below, I was able to display an external login button, authenticate with Active Directory and add a user and external login to the Umbraco database.
https://www.jdibble.co.uk/blog/securing-umbraco-backoffice-with-azure-active-directory/
This then sends you back to the /umbraco login page in a continuous loop. As described by this blog post https://our.umbraco.org/forum/developers/extending-umbraco/75256-login-uisng-azure-ad-redirects-allways-to-login-page
Has anyone faced this issue and solved it? Or have any useful suggestions?
The code being used...
public static void ConfigureBackOfficeAzureActiveDirectoryAuth(this IAppBuilder app,
string tenant, string clientId, string postLoginRedirectUri, Guid issuerId,
string caption = "Active Directory", string style = "btn-microsoft", string icon = "fa-windows")
{
var authority = string.Format(
CultureInfo.InvariantCulture,
"https://login.microsoftonline.com/{0}",
tenant);
var adOptions = new OpenIdConnectAuthenticationOptions
{
SignInAsAuthenticationType = Constants.Security.BackOfficeExternalAuthenticationType,
ClientId = clientId,
Authority = authority,
RedirectUri = postLoginRedirectUri,
AuthenticationMode = AuthenticationMode.Passive,
Notifications = new OpenIdConnectAuthenticationNotifications
{
AuthorizationCodeReceived = async context =>
{
if (System.Diagnostics.Debugger.IsAttached)
System.Diagnostics.Debugger.Break();
var userService = ApplicationContext.Current.Services.UserService;
var stuff = (List<Claim>)context.JwtSecurityToken.Claims;
var email = stuff.FirstOrDefault(x => x.Type == "unique_name").Value;
var issuer = stuff.FirstOrDefault(x => x.Type == "iss").Value;
var providerKey = stuff.FirstOrDefault(x => x.Type == "sub").Value;
var name = stuff.FirstOrDefault(x => x.Type == "name").Value;
var userManager = context.OwinContext.GetUserManager<BackOfficeUserManager>();
var user = userService.GetByEmail(email);
if (user == null)
{
var writerUserType = userService.GetUserTypeByName("writer");
user = userService.CreateUserWithIdentity(email, email, writerUserType);
}
var identity = await userManager.FindByEmailAsync(email);
if (identity.Logins.All(x => x.ProviderKey != providerKey))
{
identity.Logins.Add(new IdentityUserLogin(issuer, providerKey, user.Id));
identity.Name = name;
var result = userManager.Update(identity);
}
},
}
};
adOptions.ForUmbracoBackOffice(style, icon);
adOptions.Caption = caption;
//Need to set the auth type as the issuer path
adOptions.AuthenticationType = string.Format(
CultureInfo.InvariantCulture,
"https://sts.windows.net/{0}/",
issuerId);
adOptions.SetExternalSignInAutoLinkOptions(new ExternalSignInAutoLinkOptions(autoLinkExternalAccount: true));
app.UseOpenIdConnectAuthentication(adOptions);
}