Aflow

im 15 and in my high school marching band, jazz ensamble, wind ensamble, and some other things.
But im having trouble triple n double tonguing and playing abovethe C above tuning C. I practice alot each day, about 30 mins and i do long tones scales things from arbans book on trumpet but its not helping too much. so if anyone has tips plz tell me

thanks
aflow