private static bool HasInvalidTimestamp(TransactionViewModel transactionViewModel)
        {
            if (transactionViewModel.GetAttachmentTimestamp() == 0)
            {
                return(transactionViewModel.GetTimestamp() < MinTimestamp &&
                       transactionViewModel.GetHash() != Hash.NullHash ||
                       transactionViewModel.GetTimestamp() >
                       (TimeStamp.Now() / 1000) + MaxTimestampFuture);
            }

            return(transactionViewModel.GetAttachmentTimestamp() < MinTimestampMs ||
                   transactionViewModel.GetAttachmentTimestamp() > TimeStamp.Now() + MaxTimestampFutureMs);
        }