Amazon Prime Membership Error After Adding New Credit Card

I have been a long-time Amazon Prime customer in the United States, paying approximately $16.08 each month for the standard Prime membership, normally billed on the 16th of the month. For June, my payment was not taken, and since then I have been unable to properly add and use my new credit card for my monthly payments and purchases. For the last two days I have tried to enter my new credit card into my Amazon account. The new card appears in the system, but when I try to place an order it says my card will not be accepted and that I do not have an account, even though I am an existing Prime member. Because of this, I cannot complete any purchases and my Prime membership for June seems to be in an unclear or inactive state. I request that my new credit card be correctly added and activated as a payment method, that my Prime membership be fully reactivated and any account errors fixed, and that you confirm and correct the situation regarding my June payment as soon as possible.