Hello, and welcome!
Please let me know your safe's manufacturer and model number. Thanks!
It's possible that even though the green light comes on, your batteries aren't strong enough to open the door, so my first suggestion would be to change the batteries (alkaline, only, no recheargeable) and see if this helps. If you don't know how to replace the batteries, please let me know.
In addition, if your safe is made by Sentry and requires a key to open, in addition to the combination, make sure to remove the key after using it to pop out the cylinder, and before entering your combination. Also, make sure your handle is in the complete horizontal position before starting.
If your safe is not made by Sentry, please let me know the manufacturer and model number and I will be glad to continue.
I hope this helps.
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