Hi Hamid,
That’s so cool to see you’re in Johnny’s Altissimo course too–seems like there’s a good number of members working on it for sure; awesome. It would help to see some kind of video demo from you, that way we can see exactly what’s going right/wrong for you. As you know, there’s lots of things that we have to work on to play in this range and when we play an Altissimo note, all of those things come together. If we’re lacking in just one of the things that Johnny teaches, then it can make hitting those notes very difficult. For me, Altissimo G and G# were the hardest to play consistently because of all these adjustments we have to make in our oral cavity, embouchure, air supply from our diaphragms, etc.. There always seems to be that one note or something that each of us struggle with…keep at it though and you will get there. Johnny has provided all the tools as you know. A video demo would really help so that we can see what’s happening for you.