Please use the following command:
composer.phar config repositories.ontap vcs https://github.com/OnTap/module-mastercard
To install the latest version of the module, use the following command:
Alternatively, if you have installed using the Magento Marketplace, you can use this information: https://devdocs.magento.com/guides/v2.3/comp-mgr/extens-man/extensman-main-pg.html
This page relates to version 103.2.4
Installation help should come from your Systems Integration building your site. If this is not available to you contact On Tap.
Make a backup!
Direct installation of Magento module onto your production web site is not recommended or supported. We advise you to install this on a development version of your web site first to ensure correct operation with your particular Magento installation.
Looking for the Magento 1 version? Find it here.