My submitted assignment is blank now

Hi, I had submitted the assignment for Deep neural network week 3 and it was graded. Now that I go back to check my answers and remember how I wrote the code it’s doesn’t have any of my work in it. It’s like a new assignment again. Although it shows that it was graded before. How can I go to the version with my answers?

You can check at File-》Open if a previous version is saved there.