Charles Schwab Corp. and other retail brokerage users reported outages as a global sell-off in stocks picked up when U.S. market trading opened on Monday.

More than 15,000 users reported an outage at Schwab as of 9:50 a.m. in New York, according to the website. Downdetector, but that number had fallen to more than 3,000 outages by 10:53 a.m. in New York. A company account posted on social media platform X said that some customers “may have difficulty accessing Schwab platforms.”

Schwab fell 2.7% at 11:06 a.m. in New York on Monday. The S&P 500 index fell 3.1%.

“Some customers may experience outages on some of our platforms. We are working to resolve the issue as quickly as possible,” a Schwab spokesman said, without confirming the size or scope of the outage. Schwab had 35.6 million active brokerage accounts as of June, according to in its second quarter report.

The website Downdetector also reported problems at Fidelity Investments, which firms separately RECEIVED in an X post.

“We are aware that some customers experienced outages earlier today,” a Fidelity spokesperson said in an emailed statement. “That is now settled.”

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The global market was troubled over the weekend after Friday's weak US jobs report and the biggest drop in Japanese stocks in more than a decade.

Robinhood Markets Inc., another popular retail trading platform, was operational on Monday, according to a spokesman.