[cingo]

If you reach the correct pressure but you can not keep it, I think there is a hole (in the cups or tubes). If you bought it directly from Brava, you should call the service center and change the system now that it is under warranty. If you bought it used, you should check where the hole is: if it is in the cups, you have to repurchase them. If your system does not work, you're wasting your time!

I hope you will solve your problem soon