You would likely have to try and reach out to them via livechat or over the phone..
This is mostly a user to user forum, though there are reps around who might be able to help
Generally you should be able to add on.
There are some things you cant do, as far as i am aware.
- Account cant be in another persons name, has to be in the same name.
- Dont think business and personal can be on the same
- brand new account, may have to wait till the first billing cycle.