Chicken with runny nose for over a month

[brettzim]

I have a newish hen that has had a runny nose and sneeze since about one week after I got her (over a month ago now). I have her isolated and have medicated her with two rounds of sulmet. In-between I dosed her with a few doses of baytril. Each medication has lasted 3 days and I have waited a week or two between different medications. She seems healthy for the most part, eating, running around, but the snot in her beak co es and goes, but always comes back it seems. A couple weeks. To the sickness she seemed I'll, wings hanging and puffed up, lethargic, but that is gone now. I have given her electrolytes and vitamins as well. Not sure what to do next..