You'll need to shout it down by keeping your router at half the distance (15 to 20 feet.) Physics tell us that will give your router 4 times the signal power of the neighboring router.
If that's not possible you need to setup powerline connections. Example unit I like since it has wired and WiFi.
My neighbor has his router about 30-40 feet from my bedroom (where I stream stuff) and his signal frequently overwhelms mine. Is there anything I could use to "get his attention"
?
The problem is that his LAN was probably set up by a grand- or great grandkid and the neighbor has no clue, so even though I know his SSID, he probably doesn't.
I've tried changing channels but that hasn't helped.

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