Amazon.com Help: Reset Your Echo (3rd or 4th Generation)

Restart your device first to see if it resolves the problem. Just unplug the power adapter from the device or the outlet and then plug it back in. Video: Reset Your Echo (3rd or 4th Generation) To reset your device to its factory settings: Press and hold the Action button for 25 seconds. The light ring will pulse orange, then turn off.

https://www.amazon.com/gp/help/customer/display.html?nodeId=GCVV6G7AY7AFJF4K