My econ button for my AC/Heater won't shut off in my 1992 Buick LeSabre.?

I try to turn my air conditioner on in my car, but the econ button/light just stays on. I push it to shut it off (like I do for all the other buttons) but the light stays on and my air does not get cool. My AC does work, I had it on two days ago and everything was fine. Any suggestions?