american ecpress ***** dept

i have had my american express card for over 20 yrs and last week i noticed got a transaction notification for Netflix which i do not subscribe to . i have been calling endlessly from the day i got that notice to reverse that transaction only to be told that i need to go through to ***** dept where no one picks up and the voice mail boxes are full . and on different occasions i was told that i need to fill a dispute form and again told this is not necessary . pathetic customer service for a big name brand. no onr can help in a simple issue