I am working on ..net framework 8.0 with WebApi project and trying to enable asp versioning on the rest api endpoints. All the endpoints are broken and I am unable to figure out what is wrong. Can anyone help?

namespace Testproject1.Controllers
{
  using Testproject.Controllers.Models;
  using Asp.Versioning;
  using System.Web.Http;

  [ApiVersion(1.0)]
  [Route("api/v{version:apiVersion}/[controller]")]
  public class AgreementsController: ApiController
  {
    [Route("{accountId}")]
    public IHttpActionResult Get(string accountId) =>
        Ok(new Agreement(GetType().FullName, accountId, "1"));
  }
}


namespace Testproject1.Controllers
{
    using Testproject.Controllers.Models;
    using Asp.Versioning;
    using System.Web.Http;

    [ApiVersion(2.0)]
    [Route("api/v{version:apiVersion}/[controller]")]
    public class AgreementsControllerv2 : ApiController
    {
        [Route("{accountId}")]
        public IHttpActionResult Get(string accountId) =>
            Ok(new Agreement(GetType().FullName, accountId, "2"));
    }
}

namespace Testproject1.Controllers.V1
{
    using Testproject.Controllers.Models;
    using Asp.Versioning;
    using System.Web.Http;

    [ApiVersion(2.0)]
    [Route("api/v{version:apiVersion}/[controller]")]
    public class OrdersController : ApiController
    {
        // GET ~/v1/orders/{accountId}

        [Route("{accountId}")]
        public IHttpActionResult Get(string accountId) =>
            Ok(new Order(GetType().FullName, accountId, "1"));
    }
}

And my Startup looks like

            var configuration = new HttpConfiguration();
        var httpServer = new HttpServer(configuration);
        configuration.MapHttpAttributeRoutes();
        configuration.AddApiVersioning(
            options =>
            {
                options.ReportApiVersions = true;
                options.DefaultApiVersion = new ApiVersion(1, 0);
                options.AssumeDefaultVersionWhenUnspecified = true;
                options.ApiVersionReader = new UrlSegmentApiVersionReader();
            });

        configuration.Routes.MapHttpRoute(
            name: "VersionedApi",
            routeTemplate: "api/v{version:apiVersion}/{controller}/{id}",
            defaults: new { id = RouteParameter.Optional, version = RouteParameter.Optional });

        builder.UseWebApi(httpServer);

I am getting following response

Version: 1
http://localhost:9999/api/v1.0/agreements/1

{
“Message”: “No HTTP resource was found that matches the request URI ‘http://localhost:9999/api/v2.0/agreements/1’.”,
“MessageDetail”: “No action was found on the controller ‘Agreements’ that matches the request.”
}

Version 2:
http://localhost:9999/api/v2.0/agreements/1

{
“Message”: “No HTTP resource was found that matches the request URI ‘http://localhost:9999/api/v1.0/agreements/1’.”,
“MessageDetail”: “No action was found on the controller ‘Agreements’ that matches the request.”
}

Orders:
http://localhost:9999/api/v2.0/orders/1

{
“code”: “ApiVersionUnspecified”,
“traceId”: “776cf174-79ab-4386-a856-2f385f5f51ca”,
“type”: “https://docs.api-versioning.org/problems#unspecified”,
“title”: “Unspecified API version”,
“status”: 400,
“detail”: “An API version is required, but was not specified.”
}