There's unfortunately not quite enough to go on here to give you an exact fix.
It'll generally indicate some sort of problem with us parsing either the DB itself, or the files in the repository.
To narrow down where the problem is, can you unlink the DB, restart SSMS, then link to a new "evaluation repository", commit all objects, and refresh the commit tab?
If the problem persists, it's most likely something in your DB, but if the problem goes away, it's more likely a problem in the files in the repository.
To then narrow it down, we most likely need to see the error report as this will often indicate the object causing trouble, so can you send that in (making sure you put your email in the box) and then email firstname.lastname@example.org
to raise a ticket, referencing this forum thread?