Yeah. Sounds like she's just feeling insecure and not aggressive. Does she attack you at all? In and out of the cage? Attacking outside the enclosure is aggression. Striking only in the enclosure is being defensive. 40 gallons is pretty big. I would only keep established adults in one. And some snakes are just hissy. I have 2 that always talk but never have bitten.
Just clutter up your tank more. Add more hides. One log isn't sufficient enough. I would honestly return that. She needs 2 identical snug fitting hides that have only 1 opening. The logs don't work very well for security because they have 2 openkngs. Plus they are difficult to sanitize.Maybe even cover 3 sides of the tank with black paper or a background. The clear glass can be scary for a small snake.
And maybe even use a tank divider to make the enclosure smaller until she grows into it.
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