Amex Credit Card Complaint

Amex Credit card department,

Billing disputes North Carolina

For the last several months American Express has been applying interest to my account when there should be 0 % interest applied to this card until -/-/- I contacted American Express -/-/- regarding the most recent interest charge in the amount of - applied on -/-/-. I was informed that someone from Amex would be contacting me no later than -. No one from Amex called so I reached back out to them on -/-/- and was informed that a dispute was opened. I was not provided a dispute number/case number by phone or email. I contacted Amex on -/-/- and Amex acknowledged that no dispute was ever opened. The previous - months this issue was resolved in less than - minutes by contacting customer service. I am uncertain why Amex has failed to credit my account as no interest should be applied until -/-/-