so I did... I gave them a two star review with something along the lines of "kept pestering me to leave feedback"
then they started emailing me demanding that I remove it, which I ignored
then they started phoning the number for the delivery, which happened to be an elderly relative (as they were the order recipient)
contacted Amazon, who responded with "we'll deal with the issue and get back to you within 48 hours", which never happened
my prime subscription will now lapse (having been a prime member for more than a decade)