Kids are still finding ways to use flavored e-cigarettes despite the Food and Drug Administration’s crackdowns, according to new data from federal agencies. And even though youth vaping rates appear to be falling, 2.5 million kids still said they use the products.

The most popular brand of e-cigarettes with middle and high school-age kids is Puff Bar, according to the data, which was collected through the 2022 National Youth Tobacco Survey and published by the FDA and the Centers for Disease Control and Prevention. Puff Bar makes disposable vapes that come in a variety of flavors, and it was able to skirt FDA regulation by switching to synthetic nicotine — which the agency didn’t regulate until this year.

In April, Congress passed a law clarifying the agency’s power to regulate synthetic nicotine. Thursday, in response to the new data, the FDA announced that it issued a warning letter to Puff Bar for distributing e-cigarettes without its approval.

The agency also said that it was rejecting applications from e-cigarette company Hyde, which also sells disposable flavored vapes. The new survey data showed that Hyde was popular with middle and high school students. Vapes and e-cigarettes have to get FDA authorization before they can be sold, and the agency has spent the last year rejecting and approving applications — with rejections going to companies selling products with flavors popular with kids.

“FDA is actively working to identify violations and to swiftly seek corrective actions, particularly for products popular among youth,” Brian King, director of the FDA’s Center for Tobacco Products, said in a statement. “We will use all compliance and enforcement tools available to us, as appropriate, to protect our nation’s youth.”

The new data also confirms that Juul — which was blamed for kick-starting teen vaping in the United States — is no longer the biggest concern around youth vaping. Juul pulled its fruit flavors from the market in 2019 and now only has tobacco- and menthol-flavored products. It’s currently appealing the FDA’s decision to reject its applications. In the new survey, Juul was the third-most cited brand used by kids. Vapes with prefilled pods (like Juul) were only used by around a quarter of teens who vaped. Over half said they used disposables.

Now, the pressure is on the FDA to tackle disposable vapes. And so far, warnings like the one the company sent to Puff Bar haven’t been working, according to a Stat News investigation. Retailers are still selling hundreds of products that the agency has banned.

Despite the concerns around new products, youth vaping rates appear to be falling. The CDC said in a statement that it’s difficult to compare the data from this year’s survey to pre-pandemic data due to changes in methodology. Still, on this year’s survey, just over 9 percent of middle and high school students said they vaped in the past 30 days. That’s down from 2020 and down even further from 2018, when rates first started to spike.

But the numbers are still too high, said Deirdre Lawrence Kittner, director of the CDC’s Office on Smoking and Health, in a statement. “Our work is far from over. It’s critical that we work together to prevent youth from starting to use any tobacco product — including e-cigarettes — and help all youth who do use them, to quit.”