I have a user name and password for Office 365 Professional Plus for life. When I log in, I am informed that my password is wrong. I have the option of forgetting my password. When I exercise this option, I am told that only the administrator can change it, or he should have given the security option for self-changing password. I only have the order number but not the administrator's address. How can I change my password? Is there any provision to do so?