hi ccc i think u cant do anything in that case coz some one is copying ur id n puttin it into chat rooms.u can copy any id with certain softwares.or some one is stealing ur password regularly by trojan.try some anti trojan softwares to keep ur password a secret or try to download “stinger” its a quick scaning software.search for it in google n scan ur pc for trojans.hope it will work out.