You can verify that you're using the correct version of the Apple USB-C Charge Cable with your Mac notebook and its USB-C AC Adapter. USB-C cables rated for 29W or 30W will work with any USB-C power adapter, but won't provide enough power when connected to a power adapter that is more than 61W, such as the 96W USB-C Power Adapter. If you use a higher wattage USB-C cable, your Mac will still charge normally. For the best charging experience, you should use the USB-C charge cable that comes with your Mac notebook.