Have a bunker hill safe. battery died. lost instructions but have the key. how do i find my way into to change

A locksmith might be able to open it for a fee.

Some safes allow a battery to be connected by an external cable, but I don't know on your model.

An article suggest contacting the manufacturer using the phone number on their web site.

https://www.hunker.com/13419279/how-do-i-open-my-bunker-hill-safe-when-the-key-is-lost

Harbor Freight Tools

TECHNICAL PROBLEMS
1-888-866-5797

Monday thru Friday

7am to 4pm (Pacific Time - USA)

https://www.harborfreight.com/household.html?CatPath=All%2BProducts%252F%252F%252F%252FEverything%2BElse%2F%2F%2F%2FSafes&RequestData=CA_CategoryExpand

Hi, Sorry to tell you only Bunker Hill will be able to sort this out. Please leave me feed back: Malcolm Campbell, Thanks.

Contact Harbor Freight Tools since they are a distributer of that product.

I’m happy to assist further over the phone at https://www.6ya.com/expert/kevin_c38b47f462e94458

Change batteries ASAP because if your batteries die you will be unable to get into the safe without the key. The batteries are located inside the safe. If you can't open the safe, you can't replace the batteries!!!

There are NO replacement keys available for model #45891. We've tried. I would NOT buy this safe again for these reasons.!!!

how do i change combination on bunker hill 45891 safe, i have tried every way i can think of.

Battery died and i can't find the key or the instructions to open the safe

Check this out:
http://www.fixya.com/support/t1062111-bunker_hill_safe

(no need to re-invent the wheel, other experts have given solutions first)

If you have the small electronic Bunker Hill safe with lost keys and dead batteries, this is a potential solution... Take a hammer and strike the top of the safe while attempting to open at the same time. You may need to place on object on top of the safe such as a flip flop shoe to strike with hammer to smooth out the pressure when striking. It should pop open after several attempts.

get the key number that is listed above the key hole and then call 888-299-3427 for a replacement