Grader doesn't work in C1W3_Assignment

I submit my notebook C1W3_Assignment ( Week 3 Assignment: Implement a Quadratic Layer) and I see in the tab submitted appear the submission waiting to be evaluated.
But after a few seconds the submission disappears and it is as if I had never submitted the notebook!
I would like to clarify that: I have obtained an accuracy greater than 97% and I have re-entered the comments in the last cell of the notebook and performed the “save & Checkpoint” before using the button to submit. All as described in the instructions.

Hi @mario_amato

Please contact Courser leaner help for support. There are other learners reporting submission issue.

Hi Mario! Welcome to the community! The issue should be resolved now. Kindly retry submitting your assignment. Hope it also works for you. Thanks!

Yes, now it works fine.