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If you have a multi-meter and if possible, check the voltage and charging current of the charger. Maybe the charger which is connected to the base is faulty due to which it is not charging the batteries to the sufficient level.
Try cleaning the contact at the bottom of the handset, at the base unit and the batteries contact also.
Clean it with a sand paper if you have. Cleaning is required to remove any rust that might be causing the interference.
Can you check the adapter which is connected to the base and tell me the voltage and current ratings. Also if you see any model number on the adapter.
Yes the remote assistance would not be possible for this request. As it is sent automatically so there is no need to select that option.
You can buy the replacement charger. I am providing you the link to buy the base charger. CLICK HERE TO BUY
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