This is for an on-ground class with all assignments graded on paper. Grades for the first quiz showed up when I input them last Thursday. They still show up for the students, but do not appear in my grade book. They are there if I download as a CSV. They show in grade book history. The students can see them.
Since the students said they could see the grades I went ahead and input the quiz 2 grades. Again, they show up in grade book history, but disappear as soon as I go down to input the next student's grade.
When I open the grade book, two identical error messages appear that say "Oops - last request did not work out."
Mac OS 10.13.2. Safari 11.0.2 AND Chrome 63.0.3239.84 (?). Input Quiz 1 grades in Safari and Quiz 2 grades in Chrome.