I'm in my thrid year at University. I recently as sent in my submission on the 30th of May and it went through perfectly alright. Everything  was  it was normal. I got a similarity score. I checked a few days ago and the submission was there. But when I checked today in my canvas it shows up as if I did not submit anything and now the submission date is closed. I'm freaking out and really sad and don't know what to do. Does canvas have any issues with disappearing submission content ?