Had two of these in quick succession. The first was a phone call telling me something about being charged for Amazon Prime and if I wanted to cancel press 1. I thought 'well, I can go into the Amazon web site and cancel' so I hung up. Needless to say when I logged in via my normal route, I was not subscribing to Amazon Prime. The second, on the following day, was an email telling me there had been a log in to my account from an unknown device and I should log in _here_ check my orders and delete any I hadn't ordered. When I logged in via my normal route, there were of course no unordered orders.
The scammers do seem to be targeting Amazon customers ATM, so be alert.