Can't find doc out for signature

I sent a form out to be signed by 2 parties. The first person signed his portion. On Nov. 24 I received the standard email notification saying he'd signed and it had been sent to the other party to sign. I checked back today and the doc is nowhere to be found on Adobe Sign. I searched through the out for signature section, the cancelled/declined section, and the signed section -- it's nowhere. I've also searched using his email address and hers (signer 1 and 2). It's like it disappeared. I've used Adobe Sign many times and have never had this problem. How do I find that doc and get the signing done? How did this happen?