As for your new purchase of a Sentry safe, recommend that you contact the company directly. With questions like this asked on our site on a regular basis, Sentry would ask about the registration that was sent in by the original owner. Since this was purchased at auction, best to speak to a customer service expert at Sentry who can guide you on where to obtain the unique combination for this safe. Because of safety, each safe has its own unique combination and no expert on our site or online would have this information to share.
Contact info for Sentry can be found here on this link provided below:
I hope the information provided is found helpful as please if you could take a quick moment to rate my assistance so that I can receive credit for helping you today.