public async Task <OperationalResult <bool> > IsExist(Operational <UserQueryModel> operational, CancellationToken cancellationToken = default)
    {
        var queryModel = operational.Parameter;

        Expression <Func <User, bool> > expression = p => p.No == queryModel.UserNo;

        var count = await _userStore.CountAsync(expression, cancellationToken);

        return(OperationalResult <bool> .Ok(count > 0));
    }