Same thing happened to me when I first got my Charge 2 about 18 months ago. I thought I would have to return it, but the problem ceased after about a month. I did pretty much what you described. I ran a damp cloth over the wristband each day, then dried it. I also washed my wrist and applied lotion. I removed my Fitbit for a day or two when the skin was particularly irritated. After about a half dozen tries of this regimen, the problem stopped. I still do this every week or so, just to make sure that the irritation doesn't return. It's possible that your skin is very sensitive and that this method won't work, but it was fortunately successful for me.
