Thank you for the thread attached in your response. The issue faced above internal to the Salesforce B2C Commerce Business manager configuration. We are working for a US based site where 3DS is optional for merchants. Hence we did not enable it in our Business Manager portal. Later, we found that 3DS is mandatory for Apple Pay to work. Below is the documentation shared by Salesforce with us. https://developer.apple.com/documentation/applepayontheweb/applepaypaymentrequest/merchantcapabilities This information is neither logged in the browser console nor in the server side logs as there was no authorization event being triggered from applepay.js file hosted on Salesforce B2C Commerce instance. This has become a grey area for us to reach out both Apple and Salesforce. After enabling 3DS, we are seeing the authorization event triggered. Hope this answer helps for others who face similar issue on Apple Pay on Salesforce B2C Commerce aka Salesforce Commerce Cloud (SFCC) formerly known as Demandware.

To add further details, we created sandbox test accounts with the help of the below documentation and using test cards provided. https://developer.apple.com/apple-pay/sandbox-testing/