После создания Service Reference появляется ошибка Schema specified is not valid

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<service xmlns="http://www.w3.org/2007/app" xmlns:atom="http://www.w3.org/2005/Atom" xml:base="http://localhost:2581/WebServices/DataService.svc/">
<workspace>
<atom:title>Default</atom:title>
<collection href="UserEntryEFs">
<atom:title>UserEntryEFs</atom:title>
</collection>
<collection href="OrderItemEntryEFs">
<atom:title>OrderItemEntryEFs</atom:title>
</collection>
<collection href="OrderEntryEFs">
<atom:title>OrderEntryEFs</atom:title>
</collection>
<collection href="ItemEntryEFs">
<atom:title>ItemEntryEFs</atom:title>
</collection>
</workspace>
</service>

Request Error
The server encountered an error processing the request. The exception message is 'Schema specified is not valid. Errors: The mapping of CLR type to EDM type is ambiguous because multiple CLR types match the EDM type 'UserEntryEF'. Previously found CLR type 'AkvelonTestFirm.Entities.UserEntryEF', newly found CLR type 'AkvelonTestFirm.DataServiceReference.Us erEntryEF'. The mapping of CLR type to EDM type is ambiguous because multiple CLR types match the EDM type 'OrderItemEntryEF'. Previously found CLR type 'AkvelonTestFirm.Entities.OrderItemEntry EF', newly found CLR type 'AkvelonTestFirm.DataServiceReference.Or derItemEntryEF'. The mapping of CLR type to EDM type is ambiguous because multiple CLR types match the EDM type 'OrderEntryEF'. Previously found CLR type 'AkvelonTestFirm.Entities.OrderEntryEF', newly found CLR type 'AkvelonTestFirm.DataServiceReference.Or derEntryEF'. The mapping of CLR type to EDM type is ambiguous because multiple CLR types match the EDM type 'ItemEntryEF'. Previously found CLR type 'AkvelonTestFirm.Entities.ItemEntryEF', newly found CLR type 'AkvelonTestFirm.DataServiceReference.It emEntryEF'. The mapping of CLR type to EDM type is ambiguous because multiple CLR types match the EDM type 'ItemEntryCPUEF'. Previously found CLR type 'AkvelonTestFirm.Entities.ItemEntryCPUEF ', newly found CLR type 'AkvelonTestFirm.DataServiceReference.It emEntryCPUEF'.'. See server logs for more details. The exception stack trace is:

at System.Data.Entity.Core.Metadata.Edm.Obj ectItemCollection.LoadAssemblyFromCache( Assembly assembly, Boolean loadReferencedAssemblies, EdmItemCollection edmItemCollection, Action`1 logLoadMessage) at System.Data.Entity.Core.Metadata.Edm.Obj ectItemCollection.ExplicitLoadFromAssemb ly(Assembly assembly, EdmItemCollection edmItemCollection, Action`1 logLoadMessage) at System.Data.Entity.Core.Metadata.Edm.Met adataWorkspace.ExplicitLoadFromAssembly( Assembly assembly, ObjectItemCollection collection, Action`1 logLoadMessage) at System.Data.Entity.Core.Metadata.Edm.Met adataWorkspace.LoadFromAssembly(Assembly assembly, Action`1 logLoadMessage) at System.Data.Entity.Core.Metadata.Edm.Met adataWorkspace.LoadFromAssembly(Assembly assembly) at System.Data.Entity.Core.Metadata.Edm.Met adataOptimization.TryUpdateEntitySetMapp ingsForType(Type entityType) at System.Data.Entity.Internal.InternalCont ext.TryUpdateEntitySetMappingsForType(Ty pe entityType) at System.Data.Entity.Internal.InternalCont ext.TryGetEntitySetAndBaseTypeForType(Ty pe entityType) at System.Data.Entity.Internal.Linq.Interna lSet`1.TryInitialize() at System.Data.Entity.Internal.InternalCont ext.ForceOSpaceLoadingForKnownEntityType s() at System.Data.Entity.DbContext.System.Data .Entity.Infrastructure.IObjectContextAda pter.get_ObjectContext() at lambda_method(Closure , Object ) at System.Data.Services.Providers.DbContext Helper.GetObjectContext(Object o) at System.Data.Services.Caching.MetadataCac he`1.TryLookup(Type serviceType, Object dataContextInstance) at System.Data.Services.Providers.BaseServi ceProvider.LoadMetadata(Boolean skipServiceOperations) at System.Data.Services.Providers.EntityFra meworkDataServiceProvider2.LoadMetadata( Boolean skipServiceOperations) at System.Data.Services.Providers.EntityFra meworkDataServiceProvider2..ctor(Object dataServiceInstance, Object dataSourceInstance) at System.Data.Services.Providers.EntityFra meworkDataService`1.CreateInternalProvid er(Object dataSourceInstance) at System.Data.Services.DataService`1.Creat eMetadataAndQueryProviders(IDataServiceM etadataProvider& metadataProviderInstance, IDataServiceQueryProvider& queryProviderInstance, Object& dataSourceInstance, Boolean& isInternallyCreatedProvider) at System.Data.Services.DataService`1.Creat eProvider() at System.Data.Services.DataService`1.Ensur eProviderAndConfigForRequest() at System.Data.Services.DataService`1.Handl eRequest() at System.Data.Services.DataService`1.Proce ssRequestForMessage(Stream messageBody) at SyncInvokeProcessRequestForMessage(Objec t , Object[] , Object[] ) at System.ServiceModel.Dispatcher.SyncMetho dInvoker.Invoke(Object instance, Object[] inputs, Object[]& outputs) at System.ServiceModel.Dispatcher.DispatchO perationRuntime.InvokeBegin(MessageRpc& rpc) at System.ServiceModel.Dispatcher.Immutable DispatchRuntime.ProcessMessage5(MessageR pc& rpc) at System.ServiceModel.Dispatcher.Immutable DispatchRuntime.ProcessMessage41(Message Rpc& rpc) at System.ServiceModel.Dispatcher.Immutable DispatchRuntime.ProcessMessage4(MessageR pc& rpc) at System.ServiceModel.Dispatcher.Immutable DispatchRuntime.ProcessMessage31(Message Rpc& rpc) at System.ServiceModel.Dispatcher.Immutable DispatchRuntime.ProcessMessage3(MessageR pc& rpc) at System.ServiceModel.Dispatcher.Immutable DispatchRuntime.ProcessMessage2(MessageR pc& rpc) at System.ServiceModel.Dispatcher.Immutable DispatchRuntime.ProcessMessage11(Message Rpc& rpc) at System.ServiceModel.Dispatcher.Immutable DispatchRuntime.ProcessMessage1(MessageR pc& rpc) at System.ServiceModel.Dispatcher.MessageRp c.Process(Boolean isOperationContextSet)