When parents are logged into their Schoology parent account, their parent setup is very similar to that of their student's account. One aspect is where parents can access the courses and assignments of their student but they may be wondering why they can't open up and see the actual assignment and its details. It gives them an error that they are unable to open or view the assignment.
This is because this is not an option for Schoology parent accounts. Parents should use ParentVUE as the official gradebook of record when reviewing how well their student did on an assignment or for reviewing if that assignment was turned in.