For me I found a neuro who knows/works wirh POTS; I also had an cardiac electrophysiologist who was able to help a lot too. Ask the doctors you have met to refer you to someone they know who knows more about POTS. Mayo Clinic is great too I hear if you get the opportunity to work with them. In my experience I mostly use my doctors for beta blockers. I decided to do physical therapy on my own, started sodium supplements and got a rolliator on my own as well - unfortunately there is only so much doctors can do for POTS if it is independent of other issues (other chronic conditions; SVTs; AFIB; enlargements) so it may honestly be best to find someone who can give medication as needed and do your own treatments if possible :( It’s unfortunate but is most realistic especially if you’ve spent lots of money on doctors already. For beta blockers I recommend an EP because they have some background with POTS and should be comfortable prescribing.