1, first check the magnetic charging head of Apple Watch, there is a layer of film on top of the original one has not been torn off, if not, please tear off the film, and then charge the Apple Watch.
2. Please restart the watch once and try to charge Apple Watch again.
3, check whether the plug part of the other end of the Apple Watch charger is firmly inserted in the socket and whether it is loose, we suggest to change a plug to try, and we recommend to use the original charging plug of the iPhone to see if it can charge the Apple Watch.
4. The charging sensor on the back of the watch may also be a problem, please check if there is any dirt on the charging sensor on the back of the watch, if there is, please wipe it clean with an eyeglasses cloth before charging.