public async Task <ActionResult <IEnumerable <Transaction> > > GetTransactionDetailsByAccountID(int id)
        {
            try
            {
                IEnumerable <Transaction> result = null;
                _logger?.LogInformation(string.Format("Start GetTransactionDetailsByAccountID: {0}", id.ToString()));
                result = await _repo?.GetTransactionDetailsByAccountID(id) ?? null;

                // Check if return object was null.
                if (result == null || result?.Count() < 1)
                {
                    // Return NotFound 404 response if no account detail was found for ID.
                    _logger?.LogWarning(string.Format("Account #{0} transaction details not found!", id.ToString()));
                    return(NotFound(null));
                }

                // Return list of transactions found.
                _logger?.LogInformation(string.Format("GetTransactionDetailsByAccountID: {0} Succeeded.", id.ToString()));
                return(Ok(result.OrderByDescending(tr => tr.TimeStamp).ToList()));
            }
            catch (Exception WTF)
            {
                // Return Internal Server Error 500 on general exception.
                _logger?.LogError(WTF, "Unexpected Error in GetTransactionDetailsByAccountID!");
                return(StatusCode(StatusCodes.Status500InternalServerError));
            }
        }