Error trying to update with ASP.NET MVC5 entity framework

I have the following problem when I try to update the Gender object, it shows me the following error when I do the update, help

    try
    {
        Common.Entities.Gender gender = this.genderRepository.FindGenderId(genderModel.GenderId);

        Domain.Models.Gender myGender = new Domain.Models.Gender
        {
            GenderId = gender.GenderId,
            GenderName = genderModel.GenderName,
            CreateBy = gender.CreateBy,
            CreationDate = gender.CreationDate,
            ModifiedBy = genderModel.ModifiedBy,
            ModifiedDate = genderModel.ModifiedDate,
        };

        this.genderRepository.UpdateGender(myGender);
        serviceResult.Data = "Genero modificado.";
    }
    catch (Exception ex)
    {
        serviceResult.Data = "Ocurrio un error modificado el genero.";
        serviceResult.RegisterError(ex);
    }

    return serviceResult;
}

and this is the objecto that I believe so that I update the data to make the update

public void UpdateGender(Models.Gender myGender)
{

    this.unitOfWorkModel.Repository<Gender>().Update(new Gender
    {
        GenderId = myGender.GenderId,
        GenderName = myGender.GenderName,
        CreateBy = myGender.CreateBy,
        CreationDate = myGender.CreationDate,
        ModifiedBy = myGender.ModifiedBy,
        ModifiedDate = myGender.ModifiedDate,
    });

    this.unitOfWorkModel.Commit();
    this.unitOfWorkModel.Dispose();
}

This is the image, with the error.