...but just for today.
Amazon offers a privacy option allowing a voice command to delete recorded info. But, it is heavily limited --only allowing removal of the current day's recordings. Amz thereby gets itself off the privacy hook, but knows full well that nobody is likely to use it consistently.
As we truly only use Alexa for timers, reminders, & the rare intercom message, I do not care if Amz wants to listen in. But they were dickheads with this half-assed option, and that did bother me. So, I programmed my smarthome text-to-speech to tell Alexa to wipe the slate. It's been running a couple of months now. Works 95% of the time.