Grading error 3rd assignment

Hi,
I am getting the below error every time I submit the C2W3 assignment. Can you please tell me how to proceed.

Please see this link to learn about grader metadata.
If grader metadata is missing, refresh your workspace and try again.
See Refresh your Lab Workspace section here
If you’ve already done this, contact coursera help

Should you be unsure if this is a metadata issue or your solution is wrong, click my name and message your notebook as an attachment.

The metadata for the cell containing initialization of statistics_gen_updated is

{
  "trusted": false
}

It should also have grader metadata entry in it.
As mentioned in my previous post, if you’ve already refreshed the lab and still see this problem, contact coursera help to fix the lab environment.