Hello, and thanks for your question.
All of the Brinks safes are currently under license as "Honeywell" safes.
You can try calling customer service at 1-800-223-8566 to request a user's manual, if you are no longer in possession of yours, as this would have contained your combination; another alternative is, after providing proof of your ownership of the safe (with a notarized letter, if necessary), ask the company for the best way to open the safe with a default combination and/or order a replacement key, if the safe uses both a combination and a key.
Here is some additional contact info:
I hope you're able to get it open.
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