Indeed there is, however the option is a bit buried. Here are the steps to disable what you’re requesting.
- Open the Alexa app on your iPhone or Android phone.
- Choose More at the bottom, then Settings.
- Choose Notifications, then select Amazon Shopping.
- Turn off the option to “receive personalized recommendations and deals based on your shopping activity.
Additionally, you can also turn off “requests to rate products you’ve purchased” if you don’t want those messages, along with disabling the option to receive notifications for “Order Updates (Inc. Subscribe & Save.)” to avoid messages about saving money by subscribing for monthly deliveries.
Hope that helps you!