Get a higher bounce and don't throw your arms and feet backwards so hard

Jump up till you are at your highest point, while swinging your arms upwards you want to grab your legs and bend your knees. At this point you start forcing your shoulders backwards (instead of at the beginning). When having made a 270° rotation (75% of a circle around your own axis), start extending your legs.

when you're about to do the back flip, try to keep your head strait without throwing it back for as long as you can, for some reason this makes you go up instead of back.

Jump up and lean dont jump back

You don't flip straight away you can wait till you up at the peak or just before then make your tuck

Get a good jump and focus more on doing the flip straight up and not backwards

Do not jump so high