[HttpGet]
    public IActionResult Get([FromQuery]string email, [FromQuery]string password)
    {
        var user = _database.Set<User>().Where(x =>
            x.Email == email &&
            Database.HashPassword(password, x.Password) == true
        ).SingleOrDefault();

        if (user == null) throw new UnauthorizedException("User", "User not found.");

        var user1 = new User();

        return StatusCode(200, user.user_id); // works
        return StatusCode(200, user1);  // works
        return StatusCode(200, user);  // could not get any response
    }