Hi there and welcome
The only way to retrieve the original, factory-set and correctkey for your safe is from the manufacturer, Sentry, and you can do that by following the directions at the webpage below. You will need to provide them with your model number and serial number, in addition to some other information.
As you can see, you will also need to fill out a notary form to confirm safe ownership and prove your identity. Just click on 'Download Notary Form' from the link above, or for your convenience, you can also easily access it here:
Once you submit your information to Sentry, it should take about a week to receive your combination from them. You can request expedited service, if available.
If you need to contact Sentry's Customer Care Center for any further questions or information, you can do so with the information here:
For your convenience, here are Sentry's Customer Service phone and Fax numbers:
Customer Service: 1-***-***-****
Their hours are typically 9AM - 6PM Monday through Friday, Eastern time, but are subject to change.
If you would like any additional information or assistance, please do not hesitate to let me know.
And if you can take a second to rate my service by clicking one of the stars at the top of the screen then submit, that would be greatly appreciated.