You can delete specific voice recordings associated with your account by going to History in Settings in the Alexa App, drilling down for a specific entry, and then tapping the delete button. Or, you can delete all voice recordings associated with your account for your Harman Kardon Allure speaker, by selecting the applicable product at the Manage Your Content and Devices page at www.amazon.com/mycd. and deleting voice recordings. However, this may degrade your Alexa experience.