You can change your payment amount by following these steps:
Under the My Bills section, click on Make A Payment for the billing account you would like to pay.
Click on the account(s) you would like to pay if you have multiple accounts. The check mark indicates the account(s) you will be making a payment for. After your selection, click on Continue.
On the next page, you will be reviewing the payment. Here you can click on Edit under the Accounts column.
A pop-up will appear for the different payment amounts. Select Account Balance to pay make a full payment.
Then click on Save and then you’ll be taken back to the Review your Payment page. Then you click on Make A Payment and you’re all set!