Your charger is more than likely a fully automatic charger that knows when to reduce it's input to the batteries. Your charger light is saying that the batteries are charged as it is coming up against a resistance.
Without having access to your scooter it suggests that the batteries may well be faulty ... regardless of whether they are new or not.
Get the supplier back as soon as possible to test both the charger and the batteries.
Some years ago I used to buy batteries in bulk for scooters and disabled vehicles .. you wouldn't believe how many dead ones arrived.