Fortunately, this is a very common issue in most cameras. There a few reasons as to why your camera may not be retracting the lens however, most solutions are quite an easy fix. Most commonly it is a battery issue in which you would just need to replace the batteries. Another solution to fix it is to go on the camera's "functioning menu", go to "function set", and press "OK". This usually causes the camera to retract the lens. If neither of these common fixes work, perhaps a factory reset will help resolve the issue which is usually present in the camera manual. Hope this helps!