Zelle is used by many people to quickly and conveniently send money electronically from their credit card or bank account.

The government agency sued Zelle’s operating company and four of its partner banks (JPMorgan Chase, Bank Of America and Wells Fargo). The CFPB says the service hasn’t done enough to protect consumers from fraud.

The CFPB said the banks violated federal law through critical failures, alleging they ignored red flags that could have prevented fraud.