The Robinhood trading app crashed this week during a major U.S. trading day, preventing customers from making trades as stocks surged, an outage that lasted into Tuesday. Robinhood is blaming “stress on our infrastructure” and the “‘thundering herd’ effect” for the problems, which it vows to fix. The platform’s customers were not impressed.

Yesterday, Breitbart News reported that the online brokerage platform Robinhood suffered a major outage on Monday that lasted the entire U.S. trading day preventing customers from making trades as stocks surged. The system-wide issue began as markets opened with clients unable to access their accounts, two hours later Robinhood stated that the problem had been identified and its staff was working on the issue. By 4:00 p.m. New York time access had not been restored, and the outage continued into Tuesday’s regular trading hours.

Today, Robin Hood’s co-founders and co-CEO’s Baiju Bhatt, Vladimir Tenev, wrote in a blog post:

Our team has spent the last two days evaluating and addressing this issue. We worked as quickly as possible to restore service, but it took us a while. Too long. We now understand the cause of the outage was stress on our infrastructure—which struggled with unprecedented load. That in turn led to a “thundering herd” effect—triggering a failure of our DNS system.

Multiple factors contributed to the unprecedented load that ultimately led to the outages. The factors included, among others, highly volatile and historic market conditions; record volume; and record account sign-ups.

Our team is continuing to work to improve the resilience of our infrastructure to meet the heightened load we have been experiencing. We’re simultaneously working to reduce the interdependencies in our overall infrastructure. We’re also investing in additional redundancies in our infrastructure.

However, shortly after the platform went back online it faced another outage that left many angry customers even more upset with the trading platform:

The firm stated that it would be reaching out to customers affected by the outage to compensate them “on a case-by-case basis.” The co-CEO’s wrote in their apology letter: “Many of you depend on Robinhood for your investments, and we’re personally committed to doing all we can to operate a stable service that’s available when you need it the most.”

Read the full blog post from Robinhood here.

Lucas Nolan is a reporter for Breitbart News covering issues of free speech and online censorship. Follow him on Twitter @LucasNolan or email him at lnolan@breitbart.com