org.apache.http.ConnectionClosedException: Premature end of chunk coded message body: closing chunk expected

namespace MyLibraryOfBooks.Models{
public class Book{
    public int Id { get; set; }
    public string Name { get; set; }

    public int? GenreId { get; set; }
    public virtual Genre Genre { get; set; }
}}

namespace MyLibraryOfBooks.Models{
public class Genre{
    public int Id { get; set; }
    public string Name { get; set; }

    public virtual ICollection<Book> Books { get; set; }
}}

namespace MyLibraryOfBooks.Models{
public class AppDatabaseContext : DbContext{
    public DbSet<Book> Books { get; set; }
    public DbSet<Genre> Genres { get; set; }
    public AppDatabaseContext(){}
    public AppDatabaseContext(DbContextOptions<AppDatabaseContext> options) : base(options){
        Database.EnsureCreated())
    }
    protected override void OnModelCreating(ModelBuilder modelBuilder){
        modelBuilder.Entity<Book>()
            .HasOne(book => book.Genre)
            .WithMany(genre => genre.Books)
            .HasForeignKey(book => book.GenreId);
}}}

namespace MyLibraryOfBooks.Controllers{
[Route("[controller]")]
public class BooksController : Controller{
    private readonly AppDatabaseContext _context;
    public BooksController(AppDatabaseContext context) { _context = context; }
    [HttpGet]
    public IEnumerable<Book> Get(){
        return _context.Books.Include(book => book.Genre);
    }
    [HttpGet("{id}"]
    public IIncludableQueryable<Book, Genre> Get(int id){
        return _context.Books.Where(book=>book.Id == id).Include(book =>book.Genre);
    }
    [HttpPost]
    public void Post([FromBody] Book book){
        _context.Books.Add(book);
        _context.SaveChanges();
    }
    [HttpPut("{id}")]
    public void Put(int id, [FromBody] Book book){
        if (id != book.Id) return;
        _context.Entry(book).State = EntityState.Modified;
        _context.SaveChanges();
    }
    [HttpDelete("{id}")]
    public void Delete(int id){
        _context.Books.Remove(_context.Books.Find(id));
        _context.SaveChanges();
    }
}}

namespace MyLibraryOfBooks.Controllers{
[Route("[controller]")]
public class GenresController : Controller{
    private readonly AppDatabaseContext _context;
    public GenresController(AppDatabaseContext context){
        _context = context;
    }
    [HttpGet]
    public IEnumerable<Genre> Get(){
        return _context.Genres.Include(genre => genre.Books);
    }
    [HttpGet("{id}")]
    public IQueryable<Genre> Get(int id){
        var genre1=_context.Genres.Where(genre=>genre.Id == id).Include(genre=>genre.Books);
        return genre1;
    }
    [HttpPost]
    public void Post([FromBody] Genre genre){
        _context.Genres.Add(genre);
        _context.SaveChanges();
    }
    [HttpPut("{id}")]
    public void Put(int id, [FromBody] Genre genre){
        if (id == genre.Id) return;
        _context.Entry(genre).State = EntityState.Modified;
        _context.SaveChanges();
    }
    [HttpDelete("{id}")]
    public void Delete(int id){
        _context.Genres.Remove(_context.Genres.Find(id));
        _context.SaveChanges();
    }
}}

namespace MyLibraryOfBooks{
public class Startup{
    public Startup(IConfiguration configuration){
        Configuration = configuration;
    }
    private IConfiguration Configuration { get; }
    public void ConfigureServices(IServiceCollection services){
        services.AddCors(options =>{
            options.AddPolicy("CorsPolicy",
                builder => builder.AllowAnyOrigin()
                    .AllowAnyMethod()
                    .AllowAnyHeader()
                    .AllowCredentials());
            options.AddPolicy("AllowSpecificOrigin", policy => policy.WithOrigins("http://localhost:5000"));
            options.AddPolicy("AllowGetMethod", policy => policy.WithMethods("GET"));
        });
        services.Configure < MvcOptions > (options => {
            options.Filters.Add(new CorsAuthorizationFilterFactory("CorsPolicy"));
        });
        services.AddDbContext<AppDatabaseContext>(options =>
            options.UseMySQL("server=localhost;port=3306;UserId=root;Password=;database=usersdb7;SslMode=none"));
        services.AddMvc();
    }
    public void Configure(IApplicationBuilder app, IHostingEnvironment env){
        app.UseCors("CorsPolicy");
        if (env.IsDevelopment()){
            app.UseDeveloperExceptionPage();
        }
        app.UseMvc();
    }
}}