Quando insiro novo usuário erro:"Username '' is invalid, can only contain letters or digits.
já adicionei na minha class startup: services.Configure(options => { options.Password.RequireNonAlphanumeric = false; options.Password.RequireUppercase = false; options.Password.RequiredLength = 8; options.User.AllowedUserNameCharacters = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789-._@+"; options.User.RequireUniqueEmail = false; });