Suggest Treatment For Persistent Blocked Nose And Clogged Ear

For the past seven years I had suffered from a stuffy nose and clogged ear. It's always on the right side. I've been to countless doctors and the best ENT hospital near where I live. They've run countless tests which show there is no actual problem. No allergies, nothing.
About a year ago I was diagnosed with Hashimoto's disease and after taking medication and things were much better. I just assumed it must have been from the medicine. However, I am not 18 wks pregnant and have my thyroid checked every two weeks and the levels are perfect, but about two weeks ago my symptoms came back. The only thing I can now think of is it's winter and the cold dry air is causing it all. I'm so stumped and am just at a road block - I have no idea what to do. Any advice would be very helpful.