On Monday, Apple alerted some developers of a signing issue that’s preventing some Apple Watch apps from working correctly. The problem was first reported by MacRumors.

Here’s the email Apple’s sending out to some developers:

We’ve discovered that there was a temporary issue with the App Store signature of your binaries that affects the ability of your app to install on Apple Watch. As a result, we’re pushing an update with the proper signing to customers’ devices.

MacRumors says it isn’t sure what went wrong, although it looks like the update being pushed out will resolve the issue.

On Wednesday, Apple’s expected to announce the fourth-generation Apple Watch. Soon after, current wearable devices users should receive the watchOS 5 software update.

First announced in June, watchOS 5 offers improvements to the Siri watch face, activity competitions, auto-workout detection, Yoga and Hiking workouts, and the ability track cadence. Additionally, the update brings improved Notifications, Podcasts and Walkie-Talkie apps, student ID cards, and web-view for links.