I think you are already off to a good start. You have an interesting concept and potentially exciting stakes. My detailed critique is below. For now, I am using the term Benders, although I know you might change it! Beacon is also a good title. (By the way, we don’t use double spaces anymore. That’s a hangover from the days of the typewriter.)
PS: If you have time, please take a look at my query too. There's a link in the signature of this message.
When 17-year-old Sarah Goldmatsui (You don’t need to include her surname in the query, nor Quentin’s. Omitting the surnames will make your query more readable) starts seeing Benders, she thinks she’s crazy. She’s the only one seeing massive machines crashing through reality, dissolving everything to black. And when the world restarts after each event, she’s the only one who notices that things were different.
Her doctor insists they’re migraines, the differences afterward: simple confusion (not sure what you mean here. Confusion about what?).
I wonder if you could include the bit about migraines in your hook. For example:
Seventeen-year-old Sarah is freaking out. She has visions of massive machines crashing through reality dissolving everything to black, but her doctor insists they’re only migraines.
You can introduce the names of the machines in the next paragraph when you introduce Quentin. At the beginning Sarah doesn’t know what they are, so no need to name them in the hook. Then you can combine the two paragraphs below, including the name of the machines, how the world restarts after each Bender event, and your exciting concept about Beacons. (Well, I find it exciting LOL)
But when Sarah meets Quentin Parsons at a party, she learns
that the Benders aren’t just in her head. Quentin sees them, too, and he knows the truth:
just a typical like other teenagers with a dysfunctional home-life, uninspiring boyfriend, and stunning intellect; she’s also a Beacon like Quentin -- alien technology designed to attract the universe-destroying Benders.
Together, Sarah and Quentin must save the universe
that (do you mean ‘world’ or ‘universe’ – you’ve used both above which may cause confusion) they were designed to destroy (full stop) – nice line and nice conflict, but we need to know why. Looks like they’ve been set up with alien technology to destroy the universe they’re allocated to, but why do they now need to save it? Have they fallen in love with it, or the people in it? while navigating their own lives in realities that are often very different than the lives they’re expecting. (this last sentence is rather vague)
With every Bender event, hope for humanity dims (how?) and now
that she’s met Quentin, Sarah has a reason to care more than ever about the future (why didn’t she care before?). She’s just not sure there’s any way they can save herself, Quentin, and the universe at the same time. Exciting stakes, but the query has not clarified what’s happening. Why will she have to choose between herself, Quentin and the universe. Can she only have two of the three..?
BENDERS is YA Science Fiction and is complete at 83,000 words.