None Given

I just created an account and upon opening it saw a non-relatd person with all their private information and was aghast to say the least! This is wrong on so many levels! We can access this person's private information, and are very concerned they have access to ours. Is there a Webmaster of other IT person(s) that can immediately resolve this? I do not want to open another account for other family members now. How can this current account be closed. I am now left wondering if the bill paid was even ours.