I was hoping to get some additional information from you, but I can send you an answer now, and if you can supply the information I requested, if your safe is not made by Sentry, I can still try to help you.
If your safe is made by Sentry, the battery holder is typically on the outside of the door. If you have a round keypad, turn the outer portion to the right (clockwise), just a little bit, from the 12:00 position to the 2:00 position, remove, and inside, you will see the battery holder. Remove, carefully and replace your batteries with alkaline or lithium for electronics. Replace your battery holder and then replace your key pad, turning to the left, so it is secure, but not over-tightened.
If you have a rectangular keypad, look under it for a plastic panel with a tiny hole near the left or center. Take a pen point or the end of a paperclip and stick it in the hole, press in, and slide the plastic panel off, to the right. Inside, you will see the batter holder and repeat above instructions to change batteries, then replace the battery holder inside and slide the panel back on, to the left.
If your safe is not made by Sentry or does not have the batteries on the outside of the door, please provide this important information and I will be glad to continue.
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