The U.S. Federal Trade Commission has charged mobile banking startup Beam Financial with misleading consumers by promising 24/7 access to their funds and substantial interest rates.

Since 2018, Beam has been offering a free savings app with partners Huntington National Bank, R&T, and Dwolla that promised users they could make transfers out of their accounts and would receive their requested funds within three to five business days.

But in a civil complaint filed on Wednesday, the FTC said consumers, in many instances, “have had their money returned to them only after weeks or months of repeated complaints” or “have not had their money returned to them weeks or months later.”

“In light of this, many consumers have complained that [Beam has] simply stolen their deposits,” the suit said.

The filing — which also names Beam founder and CEO Yinan Du as a defendant — comes six months after the FTC issued a civil investigative demand to Beam seeking information about its practices for returning funds that consumers have requested to withdraw and the interest rates it has paid to consumers.

Beam advertises a minimum base interest rate of 1%, telling consumers they “can boost the interest to as high as 7.0% each day by collecting and using interest boosts.”

“Defendants’ representations that consumers will receive substantial interest rates … are false, misleading, or unsubstantiated,” the FTC alleged, noting that consumers who currently open Beam app accounts receive a base interest rate of 0.04%.

In some instances, moreover, Beam allegedly does not calculate or pay any interest at all to consumers. “For example, when a consumer requests to withdraw their money, defendants immediately stop calculating or paying interest on those funds, even if defendants do not return for consumer’s money until weeks or months later,” the commission said.

A spokeswoman for Beam told CNBC that the company is making progress getting people their money back.

But a Florida customer last week filed a consumer class action against the company and three of its vendors, including Huntington, have sued Beam in Ohio, demanding that it provide them the information necessary to return customers’ funds.