(NewsNation) — After grilling TikTok CEO Shou Zi Chew, lawmakers made a bipartisan push for legislation to ban the popular social media app. But that ban is now stalled due to legal trouble, even as elected officials are demanding to know why TikTok hired high-level executives from parent company ByteDance.

The Biden administration’s efforts to conduct a national security review and the bipartisan RESTRICT act have been hung up in Congress over legal concerns. Namely, there is a fear the RESTRICT act is so broad that individual users could face criminal penalties for violating a ban.

There has been an effort to craft alternative legislation, even as people have protested efforts to ban the app, which has 150 million users in the U.S.

TikTok has made some moves to address concerns over security, including moving data on American users to servers located in the U.S.

While Chew has remained firm in his stance that TikTok is a Singaporean company, lawmakers are raising new concerns about the app’s ties to parent company ByteDance, a Chinese company.

Most recently, Sens. Richard Blumenthal and Marsha Blackburn said they will be investigating the company’s decision to hire high-level executives formerly employed by ByteDance, particularly regarding security concerns.

The move to hire executives has lawmakers expressing concerns TikTok is maintaining close ties to ByteDance and could face pressure from the company to turn user data on Americans over to the Chinese Communist Party.

While Congress has not banned TikTok, it has been banned on U.S. government devices over national security concerns.