Came to spend our 30th wedding anniversary with m...

Came to spend our 30th wedding anniversary with my wife & stayed at the Ibis La Fayette. Paris.
Bad experience. The air Cond at our room & the hotel was broken & they never told us upfront.when we checked in & they charged us the full rate for "an air cond" room.
How can they do this? That's totally unfair.
Need to lodge a complaint?