the neck of my my saxophone

by sthembiso xaba
(johannesburg,soweto,south africa)

i have just bought a new artenis alto saxophone and i have been playing it for a few days the problem is the neck of my saxophone where the octave hole opens,when i play notes that are lower octave it produces airy sounds but what i have noticed is that its slightly open on the top hole of the neck when you press the higher octave.iam new on the saxophone family so i do not know whats the problem.when i insert the neck to the body of the saxophone i have to lift it a little higher so it can produce quality low octave sound but when i lower it down it opens slightly as i mentioned above.please anyone help me because its a new insrument