It is possible, but I don't understand your post.
If the account is in debit by £500, why would PP refund £240? It makes no sense?
If that is what happened and you hadn't had the refund you'd be in debit by £260, if you know over how many months that is you can work out how much you're underpaying, but see below.
A couple of points to help you check all is well, have a look at your statement, and see if the meter readings you've given are on the statement.
Try to give readings more often, once a month is fine when you get the reminder. It'll help you manage the account better.
Also have a look at your usage on the statement, it should give a projection on the rhs.
Your payment is very low you must be a very very low user, my guess is it's not high enough for the energy you're using, but if you get some figures from the statement and from the meter readings you can work out whether you're paying enough (the community will help if you wish).
So in answer to your question I'm sure it's legit as long as the meter readings used are correct.
Come back with some figures?
Originally Posted by Asimhussain