Why can I not access my project? I have a paid account.

It's most likely that the ownership of the project does not belong to the subscriber. In order to do this the subscriber must take possession of the project by changing the ownership of the project to them. Here are the steps to do that.

1) Make sure the subscriber is an Administrator of the project.
2) Go to 'my projects' and click on the pencil icon to edit a project.
3) Change the ownership of the project to the subscriber. If the subscribe is not in the list it means that they are not an administrator of the project. This can be changed on the 'Team Members' page of the project by another Administrator.