How to Activate American Express Functionality in Magento
To benefit from the American Express functionality, ensure that you are using version 1.24.1 of the PayPlug module (or a later version).
Beforehand, it is also necessary to have the functionality activated. You can make this request through our dedicated form.
Once this prerequisite is fulfilled, follow the steps below:
1. Navigate to your Magento back office.
2. In the menu, go to Stores > Configuration > Sales > Payment Methods > PayPlug American Express Payment.
3. Enable the option by selecting "Activate" and then click "Save Changes" (as illustrated below).
If you seek additional information regarding the American Express functionality, you can find it in our dedicated FAQ by following this link