Chime, an online banking startup with more than 5 million customers, has been suffering an outage for much of past 24 hours that has left customers without access to their money. The startup blamed the disruption on an unspecified issue with a payments processor and said data was not at risk.

The outage took down not only the company’s website and apps, but also temporarily shut off customers’ debit cards, prompting an outpouring of complaints on Twitter. The card services have since been restored.

The downtime comes as the digital bank has been growing quickly—the number of customers has almost doubled since March, to about 5 million. Chime is also in the process of raising a new funding round that could value it at more than $5 billion. A person familiar with the matter who asked not to be identified discussing private details said that the outage does not appear to have had an impact on the fundraising talks.

“We know our members trust us with their banking needs and our teams are working diligently to fully restore the mobile app,’’ Chime Chief Executive Officer Chris Britt told Bloomberg. “In the interim, we’ve been proactively communicating real-time updates with our members.”

San Francisco-based Chime is part of a growing digital banking sector that has seen rising interest from customers and global investors in recent years. Chime’s target market, according to the company, is a younger demographic whose income ranges from $35,000 to $70,000 a year and who are frustrated by the fees charged by larger brick and mortar banks. It’s a group that may be more likely to trust a startup with their money.

The downtime this week is not the only problem customers have encountered as banking moves increasingly online. Wells Fargo experienced a major systems outage in February that prevented many customers from accessing their accounts.

“Our payment processor has been experiencing issues today, resulting in our app + website being down,” Chime said in a tweet on Thursday. “We can assure you all account information remains secure, and no personal or financial data is at risk.”