If you're currently on a prepayment meter and have a debt to pay, this is likely because there were outstanding charges on your account from before you switched to a prepayment meter.
It's best to contact your energy supplier directly if you have any concerns. They will be able to investigate for you. You may be able to add the debt to your meter and pay it off alongside your monthly bills.
If you do contact your supplier please let us know by emailing support@ophelos.com.
That way, we can place your Ophelos account while you discuss your options with your supplier. While your account is on hold, we won't expect you to make any payments.
If you're worried about your energy bills you can find lots of helpful resources here.