Amex Credit Card Complaint

Amex Credit card department,

Billing disputes North Carolina

American Express sent me a bill on - - 2016 for a balance or a minimum payment due on - - 2016, I paid my bill on - - 2016 for - times the minimum payment due, however, i was charged a late fee and received a past due minimum payment for - on the - -, 2016 statement. I phoned American Express and shared my - - payment which was made on - -, 2016 and owed the minimum payment of - for -, but the company applied my payment to the - bill. I was advised that I made my payment too early, that bills had to be paid the the day after the statement date. I do not have this payment rule in any cardholder agreement for payment. I spent 4 hours on the phone being passed from agent to agent and had to pay an errorenous minimum payment and wait for - adjustment. I do not have disclosure needed from American Express about how payments are applied that are received prior to due date or how late payment and interest is applied. The removed the late payment and supposedly noted the account that - was not passed due. I asked to speak to a Manager or a Supervisor, and was put on hold by - different agents for 10 or more minutes for the another person to come on but did not identify themselves as manager or supervisor and repeated the same info. The customer service department is not located in the US and when you call corporate headquarters in -, you are transferred back to -. The written customer complaint is a PO Box # with no name attached to whom to send the written complaint.