An option for paying for a published fare with a credit card is called “Pay for My Trip.”
You can add a service fee to your booking. It will show as a separate charge on the credit card statement.
To avoid that you can use “Pay for My Trip”, you can click “Choose Pay for My Trip”. Notice that there is a 3.5% fee involved, however, it will charge the credit card in one charge. You can choose what you want the charge to appear as in the credit card statement: air booking fee, air + record locator, or agency name.
Just put in the credit card information, agree to terms, and submit payment.