Please be aware that you need to leave enough time to submit your assignments through Turnitin. The minimum amount of time required to complete an upload to Turnitin is about 5 minutes, but larger documents and busier times may mean the process can take over 15 minutes.
If you have a slow internet connection, this can further delay the completion of a submission.
Even if you start the upload before your assignment deadline, your digital receipt may not be generated until after. This will be classed as a late submission.
Leave plenty of time to complete a Turnitin submission - do NOT wait until the final 30 minutes before the assignment deadline.
See: Time Management