Before trying to remove a negative seller feedback, please consider:
Amazon only removes feedback in the following cases:
The feedback includes obscene language.
The feedback includes seller-specific personally identifiable information.
The entire feedback comment is a product review
Amazon will strike-through feedback in the following cases:
The entire feedback comment is regarding fulfillment or customer service for an order fulfilled by Amazon.
Select "Feedback" under "Performance
Choose "Request removal" if the feedback is eligible for removal
If Amazon doesn't remove the feedback automatically but you believe that the feedback is eligible for removal, you can raise a case and explain the reason why Amazon should remove the feedback.