New York (CNN Business) US senators are calling for regulators to inspect whether Robinhood misled customers in launching its new investment accounts.

The investing app last week unveiled new checking and savings accounts with a whopping 3% interest rate. Checking rates are barely above zero at many banks.

But after the announcement, the Securities Investor Protection Corporation, an industry nonprofit, said the product might not be insured . Robinhood has since pivoted to calling the service a "cash management program."

"We are concerned that rebranding Robinhood's original announcement to cash management may simply be a way to circumvent regulatory scrutiny without offering full transparency to its customers," seven Republican and Democratic lawmakers said in a letter dated Thursday.

The memo asks the Securities and Exchange Commission and the Federal Deposit Insurance Corporation to provide an "update" on how these agencies will "carefully monitor fintechs who, intentionally or not, blur financial products for competitive advantage."

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