Naah it does not nescecarily have so much to do with Syn’s school. Facebook uses Google ads to give you ads where they think you’re interested in. You maybe just googled guitar stuff a lot so they show ads of guitar schools and stuff like that. Same when you Google plane ticket to Turkmenistan you will get an as for plane tickets to Turkmenistan like a minute later when you go to Facebook, same for guitar schools, guitars etc. If you Google it Facebook will show ads on that subject.
That’s also why if you use Google privacy is pretty much a hoax and it can kinda piss me off when people cry about things messing with their privacy because they usually have social media and use Google so you barely have any left.