Hello again, and thanks for your very helpful reply.
If your batteries are dead, you will need to replace them with 4 AA alkaline or lithium for electronics batteries (do not use rechargeable). Here are the instructions to install the new batteries:
Turn the electric lock case to the right (clockwise) from
12 o’clock to 2 o’clock and remove. Insert four new batteries
as indicated, replace the electric lock case and turn to the left
Try inserting new batteries first, and let me know if this enables you to open the door. Check the battery holder for any corrosion from rust or leaked battery acid. If you find this, carefully clean it out with some rubbing alcohol on a Q-tip.
If your key is round and hollow, use it first, to pop out the cylinder inside the lock by turning it to the right and then REMOVE the key before proceeding to enter your combination. After entering your combination, press the 'Prog/Enter' button and turn the handle down within 4 seconds.
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