Amex Credit Card Complaint

Amex Credit card department,

California

-/-/16 I sent a payment check for $290.00 to American Express. It showed up on my bank statement as cleared, but AM- did not show it as received. I contacted them in - and they instructed me to send all bank statements to them which I did. In - they said the case was closed but I was not credited for the payment. My - bank contacted them and they reopened the case. I looked at the case status and they said they are investigating, again, and should have it resolved by - - 2016! .. the payment was made in - and my bank shows that it was definitely cashed by them.