@Matt, I would suggest Apple to rethink about Apple Pay integration/testing process. It is clearly visible from many raised questions that a lot of developers have issues with Apple Pay integration/testing for website. I tried to use terminal logs to have more data, but your proposed second line gives error: command: log stream --level debug --predicate 'subsystem == "com.apple.passkit”' response: log: Bad predicate (Unable to parse the format string "subsystem == "com.apple.passkit”"): subsystem == "com.apple.passkit” Thanks!

@Matt, I found the type that caused error (marked in bold): log stream --level debug --predicate 'subsystem == "com.apple.passkit”'

@Matt, could you please help to understand what might be the issue? This is what I got from log information you suggested to use: com.apple.PassKit.PaymentAuthorizationUIExtension: (PassKitCore) [com.apple.passkit:Payment] Evaluating merchant session using PROD trust policy. com.apple.PassKit.PaymentAuthorizationUIExtension: (PassKitCore) [com.apple.passkit:Payment] Application failed to provide a valid merchant session. We can't proceed to authorize the transaction. But in JSON response I got: "epochTimestamp":1621947760916,"expiresAt":1621951360916,"merchantSessionIdentifier":"SSH4C2B96FDBEB64F25BE4EFDFDAAD51803_916523AAED1343F5BC5815E12BEE9250AFFDC1A17C46B0DE5A943F0F94927C24","nonce":"8c15c0d9","merchantIdentifier":"BAF57BA4113......2728DB39845","domainName":"xxxxx.xx","displayName":"XXXXXX","signature":"308...............000000000000","operationalAnalyticsIdentifier":"xxxxxx:BAF57BA.........39845","retries":0} Tests are made with test account and with test card ending xxxx 5996. Thanks.

Hi @srdevs! Could you please elaborate more on what and how you managed it? It is so frustrating that so many people have issue with Apple Pay JS integration....