AmEx failed to adequately investigate and provide written documentation of a dispute we first filed on XX/XX/XXXX and again on XX/XX/XXXX, against merchant, XXXX XXXX XXXX, for medical equipment for which XXXX XXXX had already billed and been paid by XXXX. On XX/XX/XXXX, we filed our first dispute online regarding the transaction. We reported that on XX/XX/XXXX the merchant charged our Amex card {$150.00} without the named cardholder 's signed authorization, despite the merchant 's verbal assurance on XX/XX/XXXX that they were billing XXXX for the equipment. Several weeks into its investigation, AmEx failed to send us any written results. Instead, its online inquiry status showed the case " Closed '' as of XX/XX/XXXX, with the following statement : " A letter detailing the resolution of your inquiry was sent to you on XX/XX/XXXX. '' AmEx closed our dispute and removed its pending suspension of its {$150.00} charge. Several weeks later, we received a Summary Notice from XXXX. The notice confirmed that XXXX had paid XXXX XXXX XXXX for its invoice submitted on XX/XX/XXXX -- for the same equipment XXXX billed our AmEx card on XX/XX/XXXX. We phoned XXXX and confirmed its payment to XXXX, then, after numerous calls to XXXX, managed to speak with XXXX staff on XX/XX/XXXX. The XXXX XXXX employee claimed they could not find any record that XXXX had paid them for the equipment. They also declined our offer to forward a copy of the XXXX Summary Notice as proof of their XXXX payment, stating instead that the Manager, XXXX, would call us about our refund. Several weeks later, having never heard back from XXXX, we called AmEx to notify them that we wished to pursue our " claims and defenses '' chargeback rights for the {$150.00} charge by XXXX on the basis of discovering that on or around XX/XX/XXXX, XXXX had already billed and been paid by XXXX for the same equipment. We also asked the AmEx employee with whom we spoke to have AmEx mail us all written documentation on record regarding their investigation of our dispute filed on XX/XX/XXXX, as we 'd never received any such documentation. On XX/XX/XXXX, AmEx opened a second dispute against XXXX XXXX for their XXXX charge of {$150.00}. The next day, on XXXX, AmEx sent us an email stating : " An important message about your account is ready for you to view in the American Express Secure Message Center. To ensure your privacy is protected, you will need to log in to your account online to view it.You can also find the Secure Message Center by logging in to your account at americanexpress.com. Then, click " Manage Your Account '' and select one of your Cards to see the link to the center.The message will be available for you to view for the next 90 days. " A critical sidenote is the problem with AmEx 's instructions for viewing any " important message '' stored at its " Secure Messaging Center ''. Namely, such important information is not easily viewable online because NO such " Manage Your Account '' option exists once logged in. Thus, finding any such " important message '' requires an AmEx search -- only to find the " Secure Messaging Center '' is now renamed " Notification Center. " Once found, the " important message '' read : " ... In order for us to continue the investigation ... provide us with : A signed copy of the original charge that reflects the amount .... '' As we 'd already stated that the charge was NOT itemized nor was it authorized by the named cardholder 's signature, we could n't provide such documentation. Instead, we uploaded the XXXX Summary Notice to prove XXXX 's payment to the merchant. On XX/XX/XXXX, AmEx closed our dispute, reinstating its {$150.00} charge, apparently accepting XXXX XXXX 's duplicated resubmission of its XX/XX/XXXX FRAUDULENT claim that XXXX did not pay them and that we 'd authorized its itemized billing of {$150.00}