Signal Subscriber want to delete Review/Rating after unsubscribed in one of my signal, service desk should help delete it as it was misplaced for another signal.
signal link Here
It doesn't look like a misplaced review, because it very clearly mentions your other signal.
A review cannot be changed or deleted after the subscriber unsubscribes anyway.
The subscriber could contact Service Desk (even though doesn't deal with such matters anymore) and aks them to remove this review.