you are unlucky
but not so unlucky. you see: meganium and its family has a 87.5% chance for being a male and a 12.5% chance for being a female, so its normal to struggle with getting a female chickorita. 12.5% means you should usually get it after something like 10-15 attempts in average, but its really hard to get. you aren't doing anything wrong and there is no way to increase the chance of breeding a female starter
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