Turnitin in report that there were issues overnight. The areas affected were:
Turnitin Paper Submissions, Turnitin Feedback Studio Grading Access.
“During this time, you may experience issues when trying to submit and may also find that Similarity Reports are unavailable. We invite you to track the progress of this disruption while we work to bring service back to optimum health. We believe we’ve resolved the issue and are monitoring for anomalies now. You may still experience some issues while queued tasks are being processed.“