2002 deville. I put air cond on and most of the

2002 deville. I put air cond on and most of the time I hear a clicking noise under the dash and can't get the air to come out of the dash vents but every once in a while it does. when it did, it was warm so I charged it with the correct 134a refridgeraand only the passenger side dash vents blew cold air,not the drivers side. Also after I turned the car off and started it later,It just blew out of the bottom for a couple of days and was clicking every time I put it on. I can only get air to switch to the dash vents every once in a while.Can you help me?