I hesitate to mention this but...

In the plant world, what causes a lot of them to change sexes is stress.

If you have a female plant, and nurture her, you generally want to pull up the males in her airspace -- once they are mature enough to identify -- to keep them from pollinating her and causing excessive/any seeds.

Seedless unpollinated females are considered top of the line, in many plants.  Better consumption.*

But... if you get a blast of cold or changing temperature, or if she has to grow and really reach for the sun, or if you neglect to monitor her, you might one day find that your female is now male.  I think it can work the other way too, but mostly I've seen the gender change from female to male, under natural stressors.

Makes sense, I guess. In the human community too.  Just parking that here, since sometimes we can learn about humans from what we have observed, in the far past, in the natural world...  hth.

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*  Fruits form through an intimate developmental collaboration between ovules (the developmental precursors to seeds) and carpels (the precursors to the body of the fruit). For centuries, humans have attempted to interrupt this association to develop seedless fruits to make them easier to consume. This is a difficult task, because fruit development is usually arrested in the absence of seed formation (1). In addition, most mutations resulting in seedless fruits disappear unnoticed because sexual reproduction is precluded and intentional vegetative propagation is required to maintain seedless genotypes [as noted by Darwin (2)].