Best answer by Strutt G
Welcome to the community.
Your monthly emailed statement (not a bill) works out OUR current balance from usage, metre reads and direct debits.
Our direct debits are reviewed twice per year by PP who may or may not adjust what we pay re account in credit or debit.
The account was set up to be approx 1 month in credit hence the advanced payment.
If you need to contact PP then proceed open the help in the APP.
Open ask wattBot - First Type..."Message the Team" and post your concerns.
Could take up to 2 days for a response but often a response is sooner.
If you would like to explain further why you feel you have been overcharged then many other members will provide some feedback.
Hope this assists in some way.