Two senators sent a letter to TikTok’s chief executive on Tuesday, accusing the company of making misleading claims to Congress around how it stores and handles American user data, and demanding answers to more than a dozen questions by the end of next week.

The letter, from Senator Richard Blumenthal, Democrat of Connecticut, and Senator Marsha Blackburn, Republican of Tennessee, focused on how sensitive data about American users may be stored in China and accessed by employees there.

The lawmakers said that recent reports from The New York Times and Forbes raised questions about statements made during congressional testimony in March by Shou Chew, TikTok’s chief executive, and in an October 2021 hearing involving Michael Beckerman, TikTok’s head of public policy for the Americas. TikTok is owned by the Chinese company ByteDance.

“We are deeply troubled by TikTok’s recurring pattern of providing misleading, inaccurate or false information to Congress and its users in the United States, including in response to us during oversight hearings and letters,” they wrote.

TikTok has been working for years to convince the U.S. government that it can separate its U.S. operations and wall off American user data amid concerns that the company could provide that information to Chinese authorities.

”We are reviewing the letter,” said Alex Haurek, a spokesman for TikTok. “We remain confident in the accuracy of our testimony and responses to Congress.”

Forbes reported last month that TikTok has stored the sensitive financial information of creators, including Social Security numbers and tax IDs, on servers in China, which can be accessed by employees there. TikTok uses internal tools and databases from ByteDance to manage payments to creators who earn money through the app, Forbes said.

The Times reported earlier in the month that American user data, including drivers licenses and potentially illegal content such as child sexual abuse materials, was shared at TikTok and ByteDance through an internal messaging and collaboration tool called Lark.

The information was often available in Lark “groups” — chat rooms of employees — with thousands of members, alarming some workers because ByteDance workers in China and elsewhere could easily see the material. The Times learned that Lark data was stored on servers in China as of late last year. At the time, TikTok didn’t respond to questions about whether Lark data is currently stored in China.