ASP.NET Core change AccessDenied route

For similar problems into an ASP.NET Core 2.x web app, if the authentication is made with Azure AD /OpenID Connect, you can change the route in this way.

services.AddAuthentication(options =>...)
            .AddOpenIdConnect(options =>...)
            .AddCookie(options =>
            {
                options.AccessDeniedPath = "/path/unauthorized";
                options.LoginPath = "/path/login";
            });

Try

 services.AddIdentity<ApplicationUser, IdentityRole>(op=>op.Cookies.ApplicationCookie.AccessDeniedPath = new PathString("/InactiveSponsor"))
         .AddEntityFrameworkStores<SponsorContext>()
         .AddDefaultTokenProviders();

Or

        services.Configure<IdentityOptions>(opt =>
        {
            opt.Cookies.ApplicationCookie.LoginPath = new PathString("/aa");
            opt.Cookies.ApplicationCookie.AccessDeniedPath = new PathString("/InactiveSponsor");
            opt.Cookies.ApplicationCookie.LogoutPath = new PathString("/");
        });