Testing Apple Pay

I'm trying to integrate Apple Pay into PayPal Checkout and have followed their instructions and all is looking good. I imagined that I could test in the PayPal Sandbox with a live card (as per GooglePay) but when testing the "oncancel" callback is called. My question is, is it a requirement to have a Developer Account setup with test card numbers to test Apple Pay or can you test with live cards in the Sandbox?

Testing Apple Pay
 
 
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