In his first-ever appearance before Congress on Wednesday, Instagram CEO Adam Mosseri faced a barrage of questions from lawmakers about the social media platform’s ill-effects on children and teens. During the hearing, titled “Protecting Kids Online: Instagram and Reforms for Young Users,” members of the Senate Subcommittee on Consumer Protection, Product Safety, and Data Security grilled Mosseri on what Instagram knows about its negative impacts on young users, especially in regard to their mental health, and how its working to make the platform safer for those users. While Mosseri pointed to existing and soon-to-be-released tools on Instagram that allow users to restrict unwanted interactions and parents to limit what their kids see, senators from both parties appeared somewhat dissatisfied with his answers.