Many states are moving to guarantee COVID-19 vaccine access for their residents amid new restrictions set by the Trump administration. But when people in these states try to schedule a vaccine appointment online, as they’ve done for years, they may be out of luck: the country’s four largest retail pharmacy chains — CVS, Walgreens, Walmart, and Kroger — are still discouraging and barring some people from booking these appointments online, even in states where it’s allowed, a Lever review found.

While it may be possible to ignore these online notices or walk into these pharmacies and request a COVID-19 shot, the companies’ messaging may be sowing confusion and lowering vaccination rates among the public.

This August, Health and Human Services secretary Robert F. Kennedy Jr, an outspoken vaccine critic, limited access to COVID-19 shots to people over age sixty-five, and those six months and older with increased risk of severe illness. The move reversed earlier federal guidance that allowed anyone six months or older to receive the vaccine.