Background: I was diagnosed in August 2020 (61 yo male) with moderate sleep apnea (19.5 oahi). Using an airsense 10, my AHI was rarely above 1. This happened during the pandemic so I never had a titration. In august 2021, I found out about OSCAR from this forum. This lead to me changing my settings which improved my sleep substantially (I started waking up with a fresh dream every day and reduced movement during the night). Now the interesting part...
I was diagnosed with cervical radiculopathy (pinched nerve) in August 2019. This caused pain in my left shoulder and arm. Physical therapy was the prescribed treatment but was not working. So in January 2022, I changed my physical therapist. While at my new PT, I asked for a referral for a therapeutic massage therapist. I went to the massage guy for a couple of sessions and got impressive pain relief and mobility improvement. I WAS NOT AWARE how tight my neck was. It happened slowly over time I guess. I had no reference point. So I quickly paused the PT and started going to massage 2x per week for 2.5 months. A typical 1 hour session was to work on my neck for 30 minutes, then my shoulder/back for 30 minutes.
Coincidentally, at this time I started having skin irritation problems from the cpap mask. I tried mask covers, different masks, and ointments to treat my skin. I found the best thing was to stop using the cpap for a few days to let my skin heal. During these periods not using the cpap, I found the signs of good sleep: felt refreshed, blankets were not messed about, and I woke up with a dream. This led me to get a pulse oximeter to wear to bed so I could monitor my sleep both with and without the cpap. After another 6 months of on and off cpap usage, I stopped using the cpap. That was September 2022.
So the neck massages were the key to solving my apnea. That was A LOT of neck massaging! Now, 1.5 years later, I have done yet another year of PT, and am back with my massage guy. My 'pinched nerve' problem is still not fixed all the way. But I figured it out. I injured my lumbar as a teenager and it was never treated. Over time, this injury slowly progressed (mainly escaping my attention). The way we know this is that this multi-year rehabilitation has been like peeling an onion. My shoulder has not been sore for over a year. My hips are much improved. The focus now is the thoracic and lumber areas of my spine.
So in my case, the apnea was caused by a bigger problem. So maybe consider that point in your case. Keep trying and good luck!