someone one made a email account with my *******

someone added another device to apple id. They are my imessage,fowareding my emails. They are changing DOB, security qestions and the veri. emails that go along with it . How can i find out who is doing this? What part of the system would have the party`s (devices #). I have bin noticeing all kind of crazy info. the system dianostcis . ********

douglas

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