Possible causations:

• If the charger is defective. The charger must be showing a red or green light depending on the status of the battery. If the light is not showing, changing from red to green or staying one color, the charger may be defective.
• The battery life has deteriorated. Please use a voltmeter to verify the voltage post-charge. If it falls below the standard voltage amount, please replace the battery.
• If the charging port between the charger and battery is defective. The charging port provides electricity output between the charger and battery. If the charging port if defective, then the battery can not charge.

Issue not resolved? Feel free to reach out to our customer service team here.