SIgnalR Connects and reconnects But still throws CORS Error

I am receiving CORS errors but the Messages are still being pushed to the client. The CORS Error:

Access to resource at 'https://Signalr.example.com/notificationhub?id=l3UG4AHcZNEq1sne4s76_g&access_token=xxxx' from origin 'https://webapp.example.com' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

I have a C# .net core web API (https://Signalr.example.com) and to an Razor Webapp (client) (https://webapp.example.com) in IIS on a local network server that has binding to those two DNS entries. Locally I use https://Localhost:5001 and https://Localhost:5002 to run these two projects without any troubles. In the webapp I am using the Microsoft Javascript client . Here is the snippet of the js code to connect to the signalR API. I am using Azure AD B2C and this works properly for authentication

 var connection = new signalR.HubConnectionBuilder()
                    .withUrl(apiConfig.NotificationSignalRURL, { accessTokenFactory: () => response.accessToken })
                    .configureLogging(signalR.LogLevel.Information)
                    .withAutomaticReconnect()
                    .build();

In the web api I have set up based on all the examples I saw to solve the CORS issues. I am not sure what I am missing. SignalRAPI startup.cs Configure :

public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            Log.Logger = new LoggerConfiguration()
           .Enrich.FromLogContext()
           .WriteTo.Console()
           .CreateLogger();
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }
            app.UseCors(builder =>
            {
                builder
                    //.AllowAnyOrigin()  ***Any Origins This doesn't work***
                    .WithOrigins("https://localhost:44347", "https://localhost:5001", "https://localhost:5002", "http://localhost:5003", "http://localhost:31765", "https://webapp.example.com")
                    .AllowAnyHeader()
                    .AllowAnyMethod()
                    .AllowCredentials();
            });
            app.UseHttpsRedirection();

            app.UseRouting();
            //https://docs.microsoft.com/en-us/aspnet/core/signalr/security?view=aspnetcore-5.0

            app.UseAuthentication();
            app.UseAuthorization();


            app.UseEndpoints(endpoints =>
            {
                endpoints.MapControllers();
                endpoints.MapHub<ChatHub>("/chathub");
                endpoints.MapHub<NotificationHub>("/NotificationHub");
                //endpoints.MapHub<NotificationUserHub>("/NotificationUserHub");
            });
        }