You already have access to Nova and you’re already associated with an organization. However, you’ve been invited to associate with another organization. The process for accepting the invitation to associate with other organizations is described in this article.
Note: For reference, here’s the process you followed to access Nova and associate with an organization initially.
Any time you’re invited to associate with another organization, you receive an email that looks similar to this:
Log in to the Nova Tenant Management System (TMS) and go to My Invitations (shown below) to see your list of invitations and associations.