Course 4 week 3 assignment 2 grading problem

hello guys, assignment 2 passed all tests but grading is not working.

any help?. thanks

The grader error message is giving you a pretty strong clue of what is wrong. It’s telling you that there are some instances of “None” in your notebook that you did not replace with the correct code. Of course it’s possible that the bug is more complex than that, but that’s the place to start: search the notebook for “None” and then go from there.

Restart kernel & Clear output after submit assigment