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Failed AVS Check: 10505-This transaction cannot be processed.
I don’t use paypal, but with autherize.net you can change your security levels so that they’ll let some things pass by. Most of the time, the problem is a recent move and a billing address that doesn’t match what’s on file, but if you’ve got very high security settings, it can even be set off by a typo somewhere. Call up paypal and ask them- they’re pretty helpful