Errrrrrrrr um, not too sure not played with one for eons!
Has it a handle? Turn that and it should lock, but without combination or key its locked for good so to speak.
From memory open battery compartment ( inside door), couple of screws, think the com change instructions are there, or a reset button.
One of them had a factory code of 158A or 158 B IIRC, but test with door open. IE if you think the comm changed lock the safe with the DOOR OPEN. Then test, cheaper that way in error.
Alarm
April 2011
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