A/C clutch won't engage nor blow cold air

Have a 96 s10 4.3 liter v6 replaced the a/c compressor about 2 weeks ago had a full a/c service $95 truck blew ice cold air now compressor clutch won't turn so no cold air what I notice after having the a/c serviced the mechanics forgot to put the valve cap back on the drier so im assuming all the r-134 refrigerant blew out because the valve cap wasn't there I checked the clutch it moves freely with my hand no noise or anything