Apple wallet NFC pass with personalization

We now want to take this a step further adding Rewards Enrollment via the terminal. So scenario is:

1. customer pays with apple pay on adyen terminal
2. we check if the customer has the NFC pass in the wallet
3. if so, they earn points (regular flow which is working)
4. if not, wallet asks if you want to onboard into the program. We use personalization.json for for this and a webservice from us

We have everything setup, but the personalization isn’t working. We follow all these steps:

https://developer.apple.com/library/archive/documentation/UserExperience/Conceptual/PassKit_PG/PassPersonalization.html

The issue is that we never receive a POST request from wallet on the /personalize route we needed to set up. It simply never triggers.

We tried to do it manually from wallet using the ‘Add Personal Info’ button that appears now (because we added personalization.json to the pkpass bundle), but this triggers a message ‘Unable to personalise pass’, while it should show the personalization fields with our logo on top. See 2 attchements, one with the error, second one how it should look after clicking the ‘Add Personal Info’ button.