Apple has just released watchOS 8.1.1 for Apple Watch users.
According to the release notes, the update fixes an issue that might cause Apple Watch Series 7 units to not charge as expected.
To download the new software, you can head to General > Software Update on an Apple Watch.
Your watch needs to have more than 50 percent power and be connected to a charger. Like most Apple Watch updates, it could take anywhere from 30 minutes to an hour to complete, so be patient.