Judy:—Sounds to me like you have vacuum breaker on your hose bibb. Some have a small allen set screw that locks them to the valve, you may be able to loosen it with the right size allen wrench.. There are other types that are screwed down tight to the hose threads, and then the screw is broken off so that no one can remove the vacuum breaker. In either case, you may wind up drilling the retaining screw out in order to get it off. Lots of luck..Bud…