Amex Prepaid Card Complaint

Amex Prepaid card department,

General purpose card Unauthorized transactions/trans. issues Hawaii

The merchant put a $50.00 hold on my card, as a deposit at a hotel. The card company made a mistake and held $350.00. The merchant and myself both told AmEx that this was a mistake but Amex isnt listening. Now my account is $250.00 negative, despite that the hotel " forced the transaction '' and made it a charge of $53.00. Amex still isnt acknowledging the mistake or willing to fix it. The merchant even told them it was a mistake and tried to do everything they could to correct it but Amex refuses to make any corrections.