Amazon seem to being doing it a lot lately, removing reviews,so I do wonder if they are getting stick from sellers, they also remove the option to return items,usually after 90 days, a lot of folk in the UK complain that what they bought went faulty after 90 days and they were stuck with it, when I have had this situation I just contact Amazon (Normally a overseas call centre) and point out the UK consumer laws, they then agree to refund or replace.
I am also a Prime member and if a item turns up past their delivery date I always complain and get a months free prime, a few years back the courier company they used was so bad, I only paid for 2 months prime out of a year.
They even try and wriggle out of refunding buyers if the item was sold by a seller other than Amazon via their website, once again if you point out that it was Amazon that you paid for the item, then they cave in and deal with it, they pass the pass the problem onto the seller, but if they don't deal with it, they try and say there is nothing they can do, once again quote them the UK consumer law and they give in