They explained that the error had prevented execution of final transactions.

As of 5 p.m., two hours after the market closed, securities companies reported they were still unable to verify the closing price of stocks on the Ho Chi Minh Stock Exchange (HoSE), on which the VN-Index is based.

An error related to the trading system has prevented the execution of at-the-close (ATC) orders, which happens within the last 15 minutes of trading, from going through at the end of Tuesday’s session. ATC orders of all stocks on HoSE are currently marked as "pending" on the systems of securities companies.

A HoSE representative who wanted to remain anonymous told VnExpress that the exchange was is in the process of verifying the error.

After a similar incident at the end of January 2018, HoSE had halted trading for two consecutive sessions to verify and process trades with the securities companies.

Excluding the ATC transactions, the HoSE saw 203 stocks fall and 182 stocks rise. Total transaction volume remained high at VND7.18 trillion ($308.72 million), over half of which went to stocks outside the VN30, the basket of HoSE’s 30 highest capped tickers.

The VN30-Index fell 0.18 percent, with 18 stocks in the red and 10 in the green.

CTG of VietinBank, one of Vietnam’s three biggest state-owned banks by assets, led losses with a 2.8 percent fall. Of the other two, BID of BIDV shed 1.5 percent, while VCB of Vietcombank edged up 0.1 percent.

VRE of mall operator Vincom Retail was another major loser with 2.4 percent. VHM of its sister real estate corporation Vinhomes fell 0.3 percent, while VIC of Vietnam’s biggest private conglomerate Vingroup, their parent corporation, added 0.2 percent.

Other losers included HPG of leading steelmaker Hoa Phat Group, down 2.2 percent, CTD of construction giant Coteccons, 1.9 percent, SAB of major brewer Sabeco, 1.8 percent, and MWG of electronics retailer Mobile World, 1.6 percent.

Oil and gas saw split results with GAS of energy giant PetroVietnam Gas and PLX of petroleum distributor Petrolimex both shedding 0.8 percent, while POW of electricity generator PetroVietnam Power was one of HoSE’s largest gainers, rising 3.3 percent.

Topping gains this session was BVH of insurance giant Bao Viet Group, up 3.6 percent. It was followed by VJC of budget carrier Vietjet Air and HDB of private HDBank, both gaining 2.4 percent.

Other gainers included EIB of private Eximbank, up 2 percent, and VNM of dairy giant Vinamilk, up 1.8 percent, while the rest gained less than 0.6 percent.

Meanwhile, the HNX-Index for stocks on Hanoi Stock Exchange edged up 0.02 percent and the UPCoM-Index for stocks on Unlisted Public Companies Market fell 0.02 percent.