fixed issue #45

src/DotNetCore.CAP/Internal/ConsumerInvokerFactory.cs

 using System;
 using DotNetCore.CAP.Abstractions;
-using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
 
 namespace DotNetCore.CAP.Internal
@@ -22,16 +21,14 @@ namespace DotNetCore.CAP.Internal
         }
 
         public IConsumerInvoker CreateInvoker(ConsumerContext consumerContext)
-        {
-            using (var scope = _serviceProvider.CreateScope())
         {
             var context = new ConsumerInvokerContext(consumerContext)
             {
-                    Result = new DefaultConsumerInvoker(_logger, scope.ServiceProvider, _modelBinderFactory, consumerContext)
+                Result = new DefaultConsumerInvoker(_logger, _serviceProvider,
+                        _modelBinderFactory, consumerContext)
             };
 
             return context.Result;
         }
     }
-    }
 }
\ No newline at end of file

src/DotNetCore.CAP/Internal/IConsumerInvoker.Default.cs

@@ -35,8 +35,11 @@ namespace DotNetCore.CAP.Internal
         {
             _logger.LogDebug("Executing consumer Topic: {0}", _consumerContext.ConsumerDescriptor.MethodInfo.Name);
 
-            var obj = ActivatorUtilities.GetServiceOrCreateInstance(_serviceProvider,
-                    _consumerContext.ConsumerDescriptor.ImplTypeInfo.AsType());
+            using (var scope = _serviceProvider.CreateScope())
+            {
+                var provider = scope.ServiceProvider;
+                var serviceType = _consumerContext.ConsumerDescriptor.ImplTypeInfo.AsType();
+                var obj = ActivatorUtilities.GetServiceOrCreateInstance(provider, serviceType);
 
                 var jsonConent = _consumerContext.DeliverMessage.Content;
                 var message = Helper.FromJson<Message>(jsonConent);
@@ -56,6 +59,7 @@ namespace DotNetCore.CAP.Internal
                     await SentCallbackMessage(message.Id, message.CallbackName, result);
                 }
             }
+        }
 
         private async Task<object> ExecuteAsync(object @class)
         {