Here are some steps to troubleshoot a laptop that is not charging when plugged in:

1. Check the power cable to ensure it is securely plugged into the laptop and power source.
2. Ensure the power source is plugged in and working by plugging another device, such as a lamp, into the wall outlet.
3. Restart the device and try plugging the power cable in again.
4. Check the laptop port for any debris.
5. Try another power cable, if available.
6. Check the laptop battery and consider replacing it if it is not charging.