Apostille Verifcation Failed

I’m playing around with the Testnet NanoWallet’s Apostille service and the public audit works great, however the private audit is giving me “Verification Failed, an error occured at the signature verification.”

All I’ve done is notarized and PDF file privately, which gave me a new Apostille Formatted PDF file. I used the audit service to check that file and that’s the result I got. Anybody know what’s wrong?