Affidavit of Support(AOS) Fees

I've been trying logging in at the Dept. of State Payment Center as soon as I got the NVC case# and the IIN. But it was not on their system yet. Yesterday, May 28, I was surprised when I was able to logged in. It shows the $88 Affidavit of Support fees. So I paid right away with the use of my US Bank Account because they only accept US bank account for payment, either checking or savings. It still in the process right now and will be marked "PAID" in the next 2-3 business days. After that I need to pay for the Immigrant Visa Fees which is $404.