The system has been unstable for months, with orders simply frozen or executed very slowly, and stock prices are not displayed, forcing investors to take needless risks.

The worst happened on June 1, when there were excessive volumes and trading value topped VND21.7 trillion ($935.3 million) in just the morning session. The system sounded a warning, and HoSE was forced to suspend trading in the afternoon to prevent possible problems.

From June 2, it refused to allow traders to cancel or modify orders to prevent the system from overloading, leaving them angry and frustrated.

Now, more than a week later, leading brokerages have reallowed the use of the features though some are still enforcing limits during peak trading hours.

The Vietnam Association of Financial Investors has sent a letter to the Ministry of Finance demanding it replaces the HoSE management.

It would help find suitable foreign candidates with extensive experience to replace the current executives whose failures have been responsible for the repeated freezing of transactions.

As a result, the supply and demand mechanism failed to discover correct market prices, investors suffered losses and the country’s stock market saw its reputation damaged, it said.

HoSE is set to test a trading system bought from South Korea from June 14, and it is expected to be fully operational this year.