rec letter question

Ok, so I have a question about getting recommendation letters. I recently graduated from university and am applying to grad school so need mandatory recommendation letters. I have asked a bunch of professors that i’ve had, and most were in small classes or ones that I did well in, but none have replied besides one. I’m having a difficult time in getting anyone to respond and I don’t know why. It seems like it shouldn’t be this hard to get recommendations since professors know you need them for things like grad school ,internship, research, etc. This is really stressing me out and I don’t know what I’m doing wrong because it shouldn’t be this difficult to get rec letters. I was thinking that this is a school specific thing, b/c the profs at my school seem to be more mean and biased than at other schools. Like I’m not bashing, but i’ve noticed that the overall culture at my school is more unfriendly and somewhat racist than at others i’ve seen. Also, it’s not just me because my friends and family that have visited have said this too about the culture. I’m not going to say what school it is (pm me if you want to know), but it’s not like a lowly ranked shitty school, it’s a decently ranked university. I’m very confused as to what to what’s going on and why it’s so difficult to get rec letters when it shouldn’t be, and when I worked really hard to graduate.