Feedback removal, automated service does not work

Hello,
We are having a few problems when requesting negative/neutral ‘product only’ feedback be removed. As far as I can tell when you request feedback removal it is an automated service looking for specific wording? However we have recently been left 3 separate feedbacks that are product only reviews, and removal by Amazon has been refused, when I’ve reopened the case I have then been told that I can not do this and have to use the feedback manager, which is automated.
Any advice please??
Thanks