Apple has acknowledged problems with the Unlock with Apple Watch feature on certain iPhone 13 smartphones.

Unlock with Apple Watch is supposed to give iPhone owners an easy way to access their smartphone when they’re wearing a face mask, sunglasses, or ski goggles without having to resort to entering a passcode like some kind of caveman. All they have to do is glance at their phone when their Apple Watch is unlocked and then swipe up from the bottom of the display.

“Apple has identified an issue where Unlock with Apple Watch may not work with iPhone 13 devices,” the company said in a support document that was published on Sept. 26. “You might see ‘Unable to Communicate with Apple Watch’ if you try to unlock your iPhone while wearing a face mask, or you might not be able to set up Unlock with Apple Watch.”

Apple said it’s looking to address the problem with “an upcoming software update,” but it didn’t say if that would be iOS 15.1 or a separate release, nor did it reveal which members of the iPhone 13 lineup are susceptible to this problem. That kind of information is more important than ever now that “iPhone 13” applies to four devices across two separate product lines.

Unfortunately it doesn’t seem like there’s much iPhone owners can do to use the feature in the meantime. “Until the update is available,” Apple said, “you can turn off Unlock with Apple Watch and use your passcode to unlock your iPhone 13.”