U.S. securities regulators have issued an investor alert encouraging investors to scrutinize their account statements and trade confirmations.

The Financial Industry Regulatory Authority issued the new alert Thursday, reminding investors that reviewing their account statements not only helps them monitor their portfolios, but can also alert them to errors, or broker misconduct, such as unauthorized trading or overcharging.

The alert details, in plain language, the key elements of account statements and “red flags” that can help investors spot and avert problems; and it reminds them to ensure that the investment objective on their statement matches their actual goals. It also explains trade confirmations, and their commission disclosure requirements.

“Investors whose portfolios have taken a hit might not be keen to open their account statements, but investors should review their statements carefully — and immediately call the firm that issued the statement about any fee they do not understand or transaction they did not authorize,” said Gerri Walsh, FINRA’s vice president for investor education. “Investors should also review trade confirmations as soon as they receive them because a single keystroke can make the difference between 100 and 1,000 shares.”