Hi @tghaks,
This is something that we would not be able to assist with in the Canvas Community because we do not have access to your school's Canvas environment and individual circumstances might be unique
I would recommend that you share a screen recording or screenshot of what you are seeing with your professor and/or IT Department. You might want to consider doing that for every device where you are able to see your submission.
It might also be a good idea for you to ask if your professor could create a new assignment as an example (not worth any points) that is assigned only to you (so none of your classmates see it) and you could screen record the process that you go through (and previously went through) showing/proving that you are able to submit.
I hope you found these tips to be helpful.
-Doug