I had suffered from continuous cold, sneezing and mucous(24 X 7 X 365) for years. I used to throw and swallow a lots and lots of mucous of every color white, yellow and brown. I was diagnosed with severe sinusitis. I was under medication for long time but nothing helped.
Then I came across a yoga master in India and with techniques I was fully cured in 2 months. So according to my experience I think you should try yoga but not the body postures (asanas). You need niti and pranayam. Sorry my friend I don’t know where can you find that kind of classes in America. Most of the yoga schools in America teach asanas only.
I live in California and if you are around I wouldn’t mind helping you. I have helped few people in past including my wife.