Query letters are hard.
They’re a job application to sell a project that you’ve poured your heart, soul, and more-than-just-all-your-free-time into for months, years, or even decades.
But, if you could have told your story in 250 words or less, you wouldn’t have needed to write the whole novel!
The problem is, there are thousands of other writers who (mostly wrongly or naively) think their novel deserves to be published more than yours does. You’re reaching out to agents who’ve seen almost everything and you need to convince them that your novel is different! (Or at least written well enough that readers don’t mind)
Unfortunately, I can’t tell you how to get it right. I don’t know the secret formula either, and I suspect it’s different for every agent, and dependent on how recently that agent had lunch.
But all is not lost!