Lenovo plugged in not charging issue is very common for Lenovo users. Try below fixes
1. Power Reset Your Lenovo Laptop - First, switch off your computer. Then, unplug your computer power cable and remove the battery from your PC. Press and hold the Power button about 30 seconds, and then release it. By doing so, the left power in the computer will run out.
After that, lay your battery back and plug the power cable into the computer. Now, turn on the laptop and check if the device charges normally. If it still fails to work, try other methods immediately.
2. Check Battery Threshold - Go to the power settings on your Lenovo computer -> Select the custom threshold. -> Turn off the threshold. After that, save the change that you made and reboot your computer. At this time, the Lenovo battery not charging can be fixed.