Requested Age vs. AI Generated Age

If I write an image prompt specifying a 25-year-old man, why does the AI frequently produce an image of a man (or a woman) that looks like he (she) is in his (her) 40s or 50s? On the other hand, I often write a prompt specifying a 28-year-old and get the ridiculous notification about not generating images containing underage people.  In either case, the difference between the prompt and the result is unreasonably different. Am I missing something, or is this a bug in desperate need of adressing?