Hello, and welcome.
I'm sorry you're having a problem with opening your safe. If the round key was lost, the 'plunger' which the key is used to release, inside the keyhole, must have been 'out', if you were able to use only the combination, to open.
If, since finding the key and using it in conjunction with the combination, the safe won't open, it's possible that the plunger in the keyhole is now pushed in, or if the plunger is still out, the key must be REMOVED before entering the combination.
If you tried the combination so many times and it still won't open, the safe may have locked you out for a certain period of time as a security measure.
Can you tell me if the combination is a manual/dial one or is the safe electronic? If electronic, try replacing the batteries. If you don't know how to do this, please let me know and I will give you instructions. If the safe has a dial, you may not be using the correct dialing sequence and that's why it's not opening. I can provide you with the dialing sequence, if you let me know whether your combination has sets of 3 or 4 digits.
Do you know if the combination has ever been changed, since you have the safe or is it using the original, factory set combination?
Please try what I suggested and if it still doesn't open, reply back and I will continue to help. Do not rate, yet, in this case.
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