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Try the default combination that you seem to have cited already:
That's a guess though. Is your safe a gun safe? model 22 by Cannon is indeed a gun safe.
Cannon safe manuals should provide information - provided that you can identify your safe's model correctly - for how to open, and how to set combinations, on your safe:
But, if you do not have the combination or code, and if you have no source for it, and if it is not a default combination or code (like the one I already mentioned), then you have no way to open it if it is a good safe, except to break into it. Safes are indeed safes - only the cheapest and most worthless of them have 'tricks' that can open them without code combination nor authorization.
If you have a bill of sale for the safe with your name on it, and are thus provably the owner of the safe, you may be able to get a default or factory-set combination for your safe from the manufacturer Cannon safes, if you contact them and are willing to go through a rather stringent set of required procedures to prove you own the safe and are entitled to its default or factory-set code.