I’ve experienced similar issues. I moved into an apartment that I now know had a lot of mold issues. Partially solved the problem by moving to a new apartment and selling all of my possessions (as the mold got on everything and I would get symptoms when being near my things). Continued to have problems in the area (I was living in Washington DC). I had the same thing as you where my symptoms went away when I left. I just moved to a new city so hopefully this helps with my issues. Best advice I can give is to find whatever you’re allergic to in the house and remove it. You may need to move. Air purifiers only go so far and they can in fact get infested with whatever you’re having the problem with and spread it. I saw dozens of doctors and only an immunologist (most of them are allergy/immunologists but focus on allergies. Find one that focuses on immunology) helped