Blazor Server and SignalR and Azure AD

I am working on a web application using Blazor Server .Net 5. On my index page, I need to show the number of online users that logged into the website through Azure AD.

First, the user hits the web, and it gets redirected to Azure AD. Once the user is Authenticated in AD he/she will land on the index page. I want to show number of online users inside the app. I started using SignalR, but I am getting a very weird Error.

I am using SingalR client lib First I created the

PeoplHub : Hub{
public async Task SendMessage(string user, string message)
        {
            await Clients.All.SendAsync("ReceiveMessage", user, message);
        }

}

Then in my Index.razor I have created

hubConnection = new HubConnectionBuilder()
            .WithUrl(NavigationManager.ToAbsoluteUri("/chathub"))
            .Build();

        hubConnection.On<string, string>("ReceiveMessage", (user, message) =>
        {
            var encodedMsg = $"{user}: {message}";
            messages.Add(encodedMsg);
            InvokeAsync(StateHasChanged);
        });
         await hubConnection.StartAsync();

I have also Implemented the IAsyncDisposal

 public async ValueTask DisposeAsync()
    {
        if (hubConnection is not null)
        {
            await hubConnection.DisposeAsync();
        }
    }

in my startup I implemented

services.AddResponseCompression(opts =>
            {
                opts.MimeTypes = ResponseCompressionDefaults.MimeTypes.Concat(
                    new[] { "application/octet-stream" });
            });
app.UseResponseCompression();

endpoints.MapHub<PeopleHub>("/peoplehub");

When I run the app, I get this error message

An unhandled exception occurred while processing the request.
JsonReaderException: '<' is an invalid start of a value. LineNumber: 2 | BytePositionInLine: 0.
System.Text.Json.ThrowHelper.ThrowJsonReaderException(ref Utf8JsonReader json, ExceptionResource resource, byte nextByte, ReadOnlySpan<byte> bytes)

InvalidDataException: Invalid negotiation response received.
Microsoft.AspNetCore.Http.Connections.NegotiateProtocol.ParseResponse(ReadOnlySpan<byte> content)