Ac not working, Checked Refrigerant, What else to do?

[shevin]

I just bought a BMW x5 2003.
AC is not working I tried added refrigerant, but the PSI level was already in more than green (in yellow zone)
so I tried to empty the refrigerant and refill it again ( I thought maybe the old one is not good) and I filled it up to yellow zone ( which is about 50 PSI )


I don't see any leak, what is the next item I can check ? (on my previous cars whenever I turned on the AC I would hear the compressor noise, this one makes no noise whatsoever...) is there anything I can do myself without mechanic?