My gradebook disappeared after I deleted a section within my class...the grades show up in grade book history and all of my students show up in people. I was trying to sync my class and I just added a section for my IEP/504 students so I could have different due dates. Synergy did not like the different due dates...so I took all of the students out of the new section and then deleted the section....then I went into grades and the individual view for grade book is gone
When you say the individual view disappeared, do you mean that your gradebook is showing a grid of all your existing students and assignments? If so, you can switch back to individual view using the gradebook drop down list in the upper left corner. Lately I have had to select that 2-3 times in a row to get it to work (and the same in reverse to get back to the grid view.)
If the entire gradebook has disappeared, this is a problem for canvas support.