@deanna17 The right machine, properly fitted for your face, with the correct prescribed therapy, ought to work. So, something is amiss in your CPAP treatment. One of those three requisite components of 'successful treatment', or 'relief', is outta whack. Maybe it's something as simple as your mouth opening as you sleep, a common problem (my hand's up), which lets the volume of delivered air escape through the least resistant path, that being your open mouth over your obstructed airway down to your lungs.

May I suggest you register over at apneaboard.com forum and seek the help of the gurus over on that site. It's free, safe, and they even have a freeware app that will read your machine's delivery for you to see what needs tweaking. Again, the gurus there will help....some....maybe a whole lot.