Fidelity Investments said some customers experienced technical issues on the company’s website Monday morning as markets tumbled. Schwab.com clients also faced delays.

“There were intermittent issues” at Fidelity.com which have been resolved, a spokesperson for the Boston-based firm said.

The three main U.S. stock benchmarks all opened more than 3% lower. In intraday trading, the S&P 500 Index tumbled the most since 2018 and the Dow Jones Industrial Average erased all of its gains for the year as the spreading coronavirus stoked a global selloff.

Due to higher than usual volumes, some clients may have experienced delays as the market opened but the systems are now fine, a Charles Schwab Corp. spokesperson said.

Andrew Komarow, founding partner of Tenpath Financial Group, a registered investment adviser in Farmington, Connecticut, said he is considering switching from Fidelity after attempting to open his personal account and finding a zero balance this morning. He said one of his customers experienced the same technical issue, and was unable to trade for as long as 40 minutes after markets opened.

“If there’s a time you want to be able to log in, this morning was it,” Komarow said in a telephone interview.