My phone is connected to a charger but it doesn't charge.
(1) If your phone still has power, you'll need to see if it's connected to a cable that shows a charging symbol. If not, you will need to replace the cable and charger.
(2) When your phone shuts down automatically, it will not display the charging symbol after connecting to the charger. It will display the charging symbol after half an hour of charging, and the phone will be charged normally.
(3) If the charging symbol still not display after connecting the charger for one hour, the battery may be in sleep mode and needs to be reactivated. You can use a 5V, 2A charger to charge your phone for half an hour before turning it on.