Sandbox always returns a nonce even when incorrect info given (e.g., 911 and 99999). It should be returning the error messages, but it isn't, just a new nonce. The sandbox application ID is definitely correct. Any ideas on how to fix this?
hmm, that doesn't seem right!
Are you using a real credit card number or one of the magic testing cards?
A test card. But I found the problem. It only produces the error once you start a charge, not when you submit the card for the nonce (that always gives you a nonce). Missed that in the fine print, oops.
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