The question is... what happened in the first place? Assuming that it was properly installed, it should never come loose. The most common reason this would happen is a misfit firing pin repeatedly striking the bushing. If the gun were dry fired repeatedly this would aggravate the problem. Impacted dirt and carbon buildup can also cause this problem, but usually light strikes will put you on to the issue before the bushing is driven loose. Tapered pins and floating pins can compensate somewhat for minor misalignment of the pin and hole.
Make sure your gunsmith checks the hammer fit , pin fit and pin protrusion. Regarding epoxy and other adhesives, it can be done, but the bushing diameter usually needs to be reduced somewhat to allow for the adhesive, otherwise you will never drive it in far enough to get the bushing flush with the frame.