a) Check what power charger is using.
b) If device is not charged from very long time, then try to keep the device on charging for 1 hr
c) Ensure charging the device as it supposed to be charge
d) Charging LED (White LED) should blink while device is charging
e) Only Type-C cable need to be used to charge the device
f) Ensure continuous power supply in socket
g) Charging via Laptop or computer is recommended
h) High Power charger will cause damage to the battery
i) If there is no LED even after charging the device for 1 hr arrange replacement