I am assuming this is a Brink's safe. You used to be able to reset the combination to any 4 digits you choose by following these instructions.
Clear all previous settings by turning the dial CLOCKWISE (to the right)
3 times. We also recommend to try the procedure with your safe door open first. Then
follow these steps:
After clearing previous settings, follow these instructions:
1. Turn the dial to 0 (zero).
2. Turn the dial to the RIGHT, passing your first combination number 4
times and stopping at that number on the fifth time around.
3. Turn the dial to the LEFT, passing your second combination number 2
times and stopping at that number the third time around.
4. Turn the dial to the RIGHT, passing your third combination number 1 time
and stopping at that number the second time around.
5. Turn the dial to the LEFT, to the last combination number and STOP.
6. Insert the key in the cylinder lock and turn RIGHT to open.
You can try this and see if maybe it will work for you.
HOWEVER, Brinks was acquired by Sisco some time ago, and they now require you to send your model number, serial number and key number in a notarized letter stating that you own the safe. They can then fax,email, or snail mail you the combination. Here is their address.
2835 East Ana St.
Compton, California 90221
The other option is to call a locksmith, but that will be expensive and may leave the safe unusable.
Please let me know if you have questions.