How do I get faster in my 500?

What do you guys do to get faster in your 500? Obviously practice faster intervals and such but I'll do like 10x50s on 45 and go 34/35 the entire time and then go to a meet and swim 35/36s. I swam it today and it was absolutely horrific, going a 6:01 and mainly 37s. My best time is a 5:43 that I got in high school and I'm supposed to be a distance swimmer so I should really be in the 5:30s by now. I never seem to drop time in my 500 in high school and when I go back to club I shoot up and almost never drop down. I'm so desperate at to get this down bc it's the only thing I have going for me, my sprinting it absolutely terrible with having a high 28 as my 50 and I'm only good at like IMs, distance free, and fly.