You may have access to more than one Unsub university account, if, for example, you are a librarian at more than one institution, are consulting for multiple institutions, or your single institution has multiple accounts (as sometimes happens when a university has an account through a consortia and also a stand-alone account).
In this case, you may want to switch between institutions.
You can do this by going to the User menu in the upper right (icon looks like a profile picture) and then selecting "Your account":
From there you will see a page that lists the institution dashboards you have access to. Click the institution name to see its Unsub account:
If you want to access a Consortium Unsub dashboard because you are on the management team of a Consortium then that will be listed under the "Consortia" tab above, rather than the "Institutions" tab.