I did that for the only purpose of getting new filters (They'd only give me two at a time since that is what insurance covered).
I quickly discovered that I could buy years' worth of filters for less than one office visit, so I quit that.
Yep. I don’t buy any supplies from the supplier the doctors want me to just go online and order things I need… entire medical device infrastructure is a racket.
Once a year check up. That’s it.