Investigating unauthorised changes to shared accounts takes a lot of effort and it can be very hard to determine who is right and wrong.
As a result, the admin team will not get involved in disputes related to shared accounts. If you share your account ID with other people it is your problem if unauthorised changes are made to the account and the admin team will not investigate reports related to shared account access.
If you are not sure about the security of your account, please create a new one and use the /movechar command (see /help for more info).