ABC

For Apple Pay and any API implementation I would suggest to send any request to our dedicated support team for CSP businesschatsupport@apple.com.

Regarding Apple Pay and oAuth steps, since you will have to simulate how a brand integrates 

a) a test endpoint setup in the “Customer Service platform” 

b) a test Business Chat Accounts (see screenshot attached) connected to your test Customer Service Platform. And specify Apple Pay and OAuth 2 details. OAuth2 details will need to be verified by us. Please send and email to our email support above for approval.