At the moment we can not give feedback on the feedback that is given by someone else. Perhaps it would be nice to open an option where you can re-open an already closed 'grade'. Sometimes I see that not everyone is as sharp in reviewing homework and submitting feedback, and a student gets a grade they don't deserve. (either a better or worse grade)
The option to complain as a student about your homework should be there also to complain as someone who gives feedback, when all feedback is given.
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