Generating client code with NSwag - problem with nested classes

So I have ASP.NET Core webservice which uses MediatR to pass request from controllers to appropriate handlers. So in turn I have nested classes:

public class SomeCommand
{
    public class Request : IRequest<Response> {}

    public class Response {}

    public class Handler : IRequestHandler<Request, Response> {}
}

So, in turn, Request and Response are my DTOs.

Now I am trying to generate client package with NSwag, which ignores external classes (SomeCommand) and produces DTOs with names Request, Request1, etc., same for Response.

I use NSwag.MSBuild package to automatically generate code when building the API.

Ideally, I would like to get generated names as SomeCommand_Request or SomeCommandRequest.

I tried "AllowReferencesWithProperties": true in nswag.json configuration file, but it did not work.

Other than that, I could not find anything.