“Numerous taxpayers have reported that they cannot access their tax refunds due to Intuit’s partnership with Green Dot Bank,” Massachusetts Sen. Elizabeth Warren and New Hampshire Sen. Jeanne Shaheen said in a joint letter to Consumer Financial Protection Bureau Director Rohit Chopra, Federal Reserve Chairman Jerome Powell and Internal Revenue Service Commissioner Charles Rettig.

According to the lawmakers, Intuit, which owns TurboTax, has been depositing refunds into bank accounts opened by the tax company without the taxpayers’ direct knowledge. Those accounts, held by Austin, Texas, based Green Dot Bank, cannot be accessed by taxpayers, the senators wrote.

“While the Internal Revenue Service (IRS) online tool indicates a refund was issued, taxpayers find it difficult or impossible for them to access these funds, as the taxpayer’s own banking institution has no record of it and they have no existing banking relationship with Green Dot Bank,” they wrote.

The senators say some taxpayers who chose to pay for their TurboTax service with funds from their tax return cannot get to the remainder of their refunds and that, though there should be a mechanism to address the issue, some people are still without their cash despite the intervention of senate staffers.

“When such an event occurs, IRS technical advisors may then send the bank a formal request using Fiscal Service Form 150.1, but as the Senators state in their letter, their staff assisting impacted constituents have found the IRS cannot compel Green Dot Bank to respond to their request, leaving the taxpayer in the dark and unable to obtain any information about next steps,” Shaheen’s office said in a release along with the letter.