Account problems

I have a problem with my account, i am the only owner and i am the only one who knows the password and when i am playing a message saying you have been disconected bacause another player is using this account... i changed my passwords four times and the same is happening... when i want to enter a message says this ID is already loged want to log? or something like that.. if someone can help me please, i didnt enterd my infornation in any web or forum.