Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do what I can to provide the right answer to your question.
Is the safe jammed? i.e. do you have the combination or code, for certain, but it won't open despite signaling that it accepts the combination?
With really cheap safes, supposedly joggling the opening handle can release the catch.
With some safes - it depends upon the model and the intended use - you may need to occasionally apply a special, specialized, non-grease lubricant into the safe's latch, to allow it to not stick and to release readily.
If you would tell me the maker and model # ***** your safe, and some specifics about the circumstances, then I could advise you further. For instance, with some makes and models of safes, there is a way to retrieve a combination set at the factory, or a registered back-up combination, or the like. But this is specific to safes made by some makers.
So let me know, please, and I will advise you further. Thanks.