Windows Phone 8 allows access to private site in Office 365

I set up Office 365 on a staff members Windows Phone 8. When they access the teamsite throught their phone, they are able to access a site that is set up to only allow access to ME. They are able to access all the files, most of which are OneNote folders.

How is this possible? and more importantly, how can I fix this so others can't access sites in Office 365 that they are not authorized to see?