Replying to Flat 3 help

So for some reason I can't seem to get the flat 3 on the trampoline I just don't understand how I throw the flip and I'm really struggling in how to learn it. So far I can backflip frontflip cork 7 and misty 5 Ik its not much but I'm trying to expand my list. I really want to learn flat 3s but I just can't seem to get the hang of them does anyone have any tips on how I can learn them? Would learning another flip help as well? I'm just stuck.