Most seller feedback on Amazon cannot be edited, but can only removed. If you left a negative feedback and would like to remove it, you have 60 calendar days from the date you left the feedback. To remove your negative feedback, please do the following:
Go to Your Submitted Feedback. (For Amazon Canada and UK customers, please replace amazon.com by amazon.ca and amazon.co.uk in the URL, respectively.)
Click Remove link next to the feedback that you would like to remove. If there is no Remove option next to a comment, the 60-day removal period has expired.