VSTS build / nuget restore fails

gistfile1.txt

GatewayTimeout https://api.nuget.org/v3-flatcontainer/microsoft.aspnetcore.mvc.razor/2.0.0/microsoft.aspnetcore.mvc.razor.2.0.0.nupkg 17ms
Failed to download package 'Microsoft.AspNetCore.Mvc.Razor.2.0.0' from 'https://api.nuget.org/v3-flatcontainer/microsoft.aspnetcore.mvc.razor/2.0.0/microsoft.aspnetcore.mvc.razor.2.0.0.nupkg'.
Response status code does not indicate success: 504 (Gateway Timeout).
  GET https://api.nuget.org/v3-flatcontainer/microsoft.aspnetcore.mvc.razor/index.json
  GET https://<our_internal_nuget_server>/nuget/FindPackagesById()?id='Microsoft.AspNetCore.Mvc.Razor'
  GET https://<our_internal_nuget_server>/nuget/FindPackagesById()?id='Microsoft.AspNetCore.Mvc.Razor'
  CACHE https://<our_internal_nuget_server>/nuget/FindPackagesById()?id='System.IO.Compression'
  CACHE https://api.nuget.org/v3-flatcontainer/system.threading.thread/index.json
NuGet.Protocol.Core.Types.FatalProtocolException: The feed 'Nuget [https://api.nuget.org/v3/index.json]' lists package 'System.Threading.Thread.4.3.0' but multiple attempts to download the nupkg have failed. The feed is either invalid or required packages were removed while the current operation was in progress. Verify the package exists on the feed and try again. ---> NuGet.Protocol.PackageNotFoundProtocolException: Unable to find package 'System.Threading.Thread.4.3.0'.
   at NuGet.Protocol.FindPackagesByIdNupkgDownloader.<GetNuspecReaderFromNupkgAsync>d__6.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.Protocol.HttpFileSystemBasedFindPackageByIdResource.<GetDependencyInfoAsync>d__7.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.Commands.SourceRepositoryDependencyProvider.<GetDependenciesCoreAsync>d__19.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.Commands.SourceRepositoryDependencyProvider.<>c__DisplayClass18_0.<<GetDependenciesAsync>b__0>d.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.Commands.SourceRepositoryDependencyProvider.<GetDependenciesAsync>d__18.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.DependencyResolver.ResolverUtility.<CreateGraphItemAsync>d__2.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.DependencyResolver.ResolverUtility.<FindLibraryEntryAsync>d__1.MoveNext()
   --- End of inner exception stack trace ---
   at NuGet.DependencyResolver.ResolverUtility.<FindLibraryEntryAsync>d__1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.DependencyResolver.RemoteDependencyWalker.<CreateGraphNode>d__3.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.DependencyResolver.RemoteDependencyWalker.<CreateGraphNode>d__3.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.DependencyResolver.RemoteDependencyWalker.<CreateGraphNode>d__3.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.DependencyResolver.RemoteDependencyWalker.<CreateGraphNode>d__3.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.Commands.ProjectRestoreCommand.<WalkDependenciesAsync>d__5.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.Commands.ProjectRestoreCommand.<TryRestore>d__3.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.Commands.RestoreCommand.<ExecuteRestoreAsync>d__19.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.Commands.RestoreCommand.<ExecuteAsync>d__8.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.Commands.RestoreRunner.<ExecuteAsync>d__7.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.Commands.RestoreRunner.<ExecuteAndCommitAsync>d__6.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.Commands.RestoreRunner.<CompleteTaskAsync>d__9.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.Commands.RestoreRunner.<RunAsync>d__2.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.Commands.RestoreRunner.<RunAsync>d__0.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.Commands.RestoreRunner.<RunAsync>d__1.MoveNext()
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at NuGet.CommandLine.RestoreCommand.<ExecuteCommandAsync>d__34.MoveNext()